diff --git a/cli.js b/cli.js
index 9244259..8a9306f 100755
--- a/cli.js
+++ b/cli.js
@@ -916,7 +916,7 @@ async function zkeyChallangeContribute(params, options) {
     let challangeName;
     let responseName;
 
-    const curve = curves.getCurveFromName(params[0]);
+    const curve = await curves.getCurveFromName(params[0]);
 
     challangeName = params[1];
 
diff --git a/src/mpc_applykey.js b/src/mpc_applykey.js
index 2be6094..fc22b46 100644
--- a/src/mpc_applykey.js
+++ b/src/mpc_applykey.js
@@ -26,7 +26,7 @@ async function applyKeyToSection(fdOld, sections, fdNew, idSection, curve, group
         buff = await fdOld.read(n*sG);
         buff = await G.batchApplyKey(buff, t, inc);
         await fdNew.write(buff);
-        t = curve.Fr.mul(t, curve.Fr.pow(inc, n));
+        t = curve.Fr.mul(t, curve.Fr.exp(inc, n));
     }
 
     await binFileUtils.endWriteSection(fdNew);
diff --git a/src/zkey_beacon.js b/src/zkey_beacon.js
index eac0a3f..80c0d28 100644
--- a/src/zkey_beacon.js
+++ b/src/zkey_beacon.js
@@ -33,8 +33,7 @@ module.exports = async function beacon(zkeyNameOld, zkeyNameNew, name, numIterat
     const {fd: fdOld, sections: sections} = await binFileUtils.readBinFile(zkeyNameOld, "zkey", 2);
     const zkey = await zkeyUtils.readHeader(fdOld, sections, "groth16");
 
-    const curve = getCurve(zkey.q);
-    await curve.loadEngine();
+    const curve = await getCurve(zkey.q);
 
     const mpcParams = await zkeyUtils.readMPCParams(fdOld, curve, sections);
 
@@ -52,15 +51,15 @@ module.exports = async function beacon(zkeyNameOld, zkeyNameNew, name, numIterat
     curContribution.delta = {};
     curContribution.delta.prvKey = curve.Fr.fromRng(rng);
     curContribution.delta.g1_s = curve.G1.toAffine(curve.G1.fromRng(rng));
-    curContribution.delta.g1_sx = curve.G1.toAffine(curve.G1.timesScalar(curContribution.delta.g1_s, curContribution.delta.prvKey));
+    curContribution.delta.g1_sx = curve.G1.toAffine(curve.G1.timesFr(curContribution.delta.g1_s, curContribution.delta.prvKey));
     utils.hashG1(transcriptHasher, curve, curContribution.delta.g1_s);
     utils.hashG1(transcriptHasher, curve, curContribution.delta.g1_sx);
     curContribution.transcript = transcriptHasher.digest();
     curContribution.delta.g2_sp = hashToG2(curve, curContribution.transcript);
-    curContribution.delta.g2_spx = curve.G2.toAffine(curve.G2.timesScalar(curContribution.delta.g2_sp, curContribution.delta.prvKey));
+    curContribution.delta.g2_spx = curve.G2.toAffine(curve.G2.timesFr(curContribution.delta.g2_sp, curContribution.delta.prvKey));
 
-    zkey.vk_delta_1 = curve.G1.timesScalar(zkey.vk_delta_1, curContribution.delta.prvKey);
-    zkey.vk_delta_2 = curve.G2.timesScalar(zkey.vk_delta_2, curContribution.delta.prvKey);
+    zkey.vk_delta_1 = curve.G1.timesFr(zkey.vk_delta_1, curContribution.delta.prvKey);
+    zkey.vk_delta_2 = curve.G2.timesFr(zkey.vk_delta_2, curContribution.delta.prvKey);
 
     curContribution.deltaAfter = zkey.vk_delta_1;
 
diff --git a/src/zkey_challangecontribute.js b/src/zkey_challangecontribute.js
index 449826b..a2f9383 100644
--- a/src/zkey_challangecontribute.js
+++ b/src/zkey_challangecontribute.js
@@ -44,10 +44,10 @@ async function challangeContribute(curve, challangeFilename, responesFileName, e
     await copy(sG2); // beta2
     await copy(sG2); // gamma2
     const oldDelta1 = await readG1();
-    const delta1 = curve.G1.timesScalar(oldDelta1, delta);
+    const delta1 = curve.G1.timesFr(oldDelta1, delta);
     await writeG1(delta1);
     const oldDelta2 = await readG2();
-    const delta2 = curve.G2.timesScalar(oldDelta2, delta);
+    const delta2 = curve.G2.timesFr(oldDelta2, delta);
     await writeG2(delta2);
 
     // IC
@@ -108,12 +108,12 @@ async function challangeContribute(curve, challangeFilename, responesFileName, e
     curContribution.delta = {};
     curContribution.delta.prvKey = delta;
     curContribution.delta.g1_s = curve.G1.toAffine(curve.G1.fromRng(rng));
-    curContribution.delta.g1_sx = curve.G1.toAffine(curve.G1.timesScalar(curContribution.delta.g1_s, delta));
+    curContribution.delta.g1_sx = curve.G1.toAffine(curve.G1.timesFr(curContribution.delta.g1_s, delta));
     utils.hashG1(transcriptHasher, curve, curContribution.delta.g1_s);
     utils.hashG1(transcriptHasher, curve, curContribution.delta.g1_sx);
     curContribution.transcript = transcriptHasher.digest();
     curContribution.delta.g2_sp = hashToG2(curve, curContribution.transcript);
-    curContribution.delta.g2_spx = curve.G2.toAffine(curve.G2.timesScalar(curContribution.delta.g2_sp, delta));
+    curContribution.delta.g2_spx = curve.G2.toAffine(curve.G2.timesFr(curContribution.delta.g2_sp, delta));
     curContribution.deltaAfter = delta1;
     curContribution.type = 0;
     mpcParams.contributions.push(curContribution);
diff --git a/src/zkey_contribute.js b/src/zkey_contribute.js
index 9174f29..501d3d3 100644
--- a/src/zkey_contribute.js
+++ b/src/zkey_contribute.js
@@ -14,8 +14,7 @@ module.exports  = async function phase2contribute(zkeyNameOld, zkeyNameNew, name
     const {fd: fdOld, sections: sections} = await binFileUtils.readBinFile(zkeyNameOld, "zkey", 2);
     const zkey = await zkeyUtils.readHeader(fdOld, sections, "groth16");
 
-    const curve = getCurve(zkey.q);
-    await curve.loadEngine();
+    const curve = await getCurve(zkey.q);
 
     const mpcParams = await zkeyUtils.readMPCParams(fdOld, curve, sections);
 
@@ -34,15 +33,15 @@ module.exports  = async function phase2contribute(zkeyNameOld, zkeyNameNew, name
     curContribution.delta = {};
     curContribution.delta.prvKey = curve.Fr.fromRng(rng);
     curContribution.delta.g1_s = curve.G1.toAffine(curve.G1.fromRng(rng));
-    curContribution.delta.g1_sx = curve.G1.toAffine(curve.G1.timesScalar(curContribution.delta.g1_s, curContribution.delta.prvKey));
+    curContribution.delta.g1_sx = curve.G1.toAffine(curve.G1.timesFr(curContribution.delta.g1_s, curContribution.delta.prvKey));
     utils.hashG1(transcriptHasher, curve, curContribution.delta.g1_s);
     utils.hashG1(transcriptHasher, curve, curContribution.delta.g1_sx);
     curContribution.transcript = transcriptHasher.digest();
     curContribution.delta.g2_sp = hashToG2(curve, curContribution.transcript);
-    curContribution.delta.g2_spx = curve.G2.toAffine(curve.G2.timesScalar(curContribution.delta.g2_sp, curContribution.delta.prvKey));
+    curContribution.delta.g2_spx = curve.G2.toAffine(curve.G2.timesFr(curContribution.delta.g2_sp, curContribution.delta.prvKey));
 
-    zkey.vk_delta_1 = curve.G1.timesScalar(zkey.vk_delta_1, curContribution.delta.prvKey);
-    zkey.vk_delta_2 = curve.G2.timesScalar(zkey.vk_delta_2, curContribution.delta.prvKey);
+    zkey.vk_delta_1 = curve.G1.timesFr(zkey.vk_delta_1, curContribution.delta.prvKey);
+    zkey.vk_delta_2 = curve.G2.timesFr(zkey.vk_delta_2, curContribution.delta.prvKey);
 
     curContribution.deltaAfter = zkey.vk_delta_1;
 
diff --git a/src/zkey_export_bellman.js b/src/zkey_export_bellman.js
index 9752ff1..909b3d3 100644
--- a/src/zkey_export_bellman.js
+++ b/src/zkey_export_bellman.js
@@ -9,8 +9,7 @@ module.exports  = async function phase2exportMPCParams(zkeyName, mpcparamsName,
     const {fd: fdZKey, sections: sectionsZKey} = await binFileUtils.readBinFile(zkeyName, "zkey", 2);
     const zkey = await zkeyUtils.readHeader(fdZKey, sectionsZKey, "groth16");
 
-    const curve = getCurve(zkey.q);
-    await curve.loadEngine();
+    const curve = await getCurve(zkey.q);
     const sG1 = curve.G1.F.n8*2;
     const sG2 = curve.G2.F.n8*2;
 
@@ -42,7 +41,7 @@ module.exports  = async function phase2exportMPCParams(zkeyName, mpcparamsName,
 
     let buffBasesH_Tau;
     buffBasesH_Tau = await curve.G1.fft(buffBasesH_Lodd, "affine", "jacobian", verbose ? console.log : undefined);
-    buffBasesH_Tau = await curve.G1.batchApplyKey(buffBasesH_Tau, curve.Fr.neg(curve.Fr.e(2)), curve.PFr.w[zkey.power+1], "jacobian", "affine", verbose ? console.log : undefined);
+    buffBasesH_Tau = await curve.G1.batchApplyKey(buffBasesH_Tau, curve.Fr.neg(curve.Fr.e(2)), curve.Fr.w[zkey.power+1], "jacobian", "affine", verbose ? console.log : undefined);
 
     // Remove last element.  (The degree of H will be allways m-2)
     buffBasesH_Tau = buffBasesH_Tau.slice(0, buffBasesH_Tau.byteLength - sG1);
diff --git a/src/zkey_import_bellman.js b/src/zkey_import_bellman.js
index 4125e53..4a9da19 100644
--- a/src/zkey_import_bellman.js
+++ b/src/zkey_import_bellman.js
@@ -9,8 +9,7 @@ module.exports  = async function phase2importMPCParams(zkeyNameOld, mpcparamsNam
     const {fd: fdZKeyOld, sections: sectionsZKeyOld} = await binFileUtils.readBinFile(zkeyNameOld, "zkey", 2);
     const zkeyHeader = await zkeyUtils.readHeader(fdZKeyOld, sectionsZKeyOld, "groth16");
 
-    const curve = getCurve(zkeyHeader.q);
-    await curve.loadEngine();
+    const curve = await getCurve(zkeyHeader.q);
     const sG1 = curve.G1.F.n8*2;
     const sG2 = curve.G2.F.n8*2;
 
@@ -39,6 +38,16 @@ module.exports  = async function phase2importMPCParams(zkeyNameOld, mpcparamsNam
         c.delta.g1_sx = await readG1(fdMPCParams);
         c.delta.g2_spx = await readG2(fdMPCParams);
         c.transcript = await fdMPCParams.read(64);
+        if (i<oldMPCParams.contributions.length) {
+            c.type = oldMPCParams.contributions[i].type;
+            if (c.type==1) {
+                c.beaconHash = oldMPCParams.contributions[i].beaconHash;
+                c.numIterationsExp = oldMPCParams.contributions[i].numIterationsExp;
+            }
+            if (oldMPCParams.contributions[i].name) {
+                c.name = oldMPCParams.contributions[i].name;
+            }
+        }
         newMPCParams.contributions.push(c);
     }
 
@@ -98,7 +107,7 @@ module.exports  = async function phase2importMPCParams(zkeyNameOld, mpcparamsNam
     buffH = new Uint8Array(zkeyHeader.domainSize*sG1);
     buffH.set(buffTauLEM);   // Let the last one to zero.
     const n2Inv = curve.Fr.neg(curve.Fr.inv(curve.Fr.e(2)));
-    const wInv = curve.Fr.inv(curve.PFr.w[zkeyHeader.power+1]);
+    const wInv = curve.Fr.inv(curve.Fr.w[zkeyHeader.power+1]);
     buffH = await curve.G1.batchApplyKey(buffH, n2Inv, wInv, "affine", "jacobian", verbose ? console.log : undefined);
     buffH = await curve.G1.ifft(buffH, "jacobian", "affine", verbose ? console.log : undefined);
     await binFileUtils.startWriteSection(fdZKeyNew, 9);
diff --git a/src/zkey_utils.js b/src/zkey_utils.js
index 17fe02f..a3d5503 100644
--- a/src/zkey_utils.js
+++ b/src/zkey_utils.js
@@ -46,7 +46,7 @@ async function writeHeader(fd, zkey) {
     // Write the Groth header section
     ///////////
 
-    const curve = getCurve(zkey.q);
+    const curve = await getCurve(zkey.q);
 
     await binFileUtils.startWriteSection(fd, 2);
     const primeQ = curve.q;
diff --git a/src/zkey_verify.js b/src/zkey_verify.js
index fc5d67a..66dc43e 100644
--- a/src/zkey_verify.js
+++ b/src/zkey_verify.js
@@ -20,8 +20,7 @@ module.exports  = async function phase2verify(r1csFileName, pTauFileName, zkeyFi
     const {fd, sections} = await binFileUtils.readBinFile(zkeyFileName, "zkey", 2);
     const zkey = await zkeyUtils.readHeader(fd, sections, "groth16");
 
-    const curve = getCurve(zkey.q);
-    await curve.loadEngine();
+    const curve = await getCurve(zkey.q);
     const sG1 = curve.G1.F.n8*2;
     const sG2 = curve.G2.F.n8*2;
 
@@ -60,7 +59,7 @@ module.exports  = async function phase2verify(r1csFileName, pTauFileName, zkeyFi
             const rng = misc.rngFromBeaconParams(c.beaconHash, c.numIterationsExp);
             const expected_prvKey = curve.Fr.fromRng(rng);
             const expected_g1_s = curve.G1.toAffine(curve.G1.fromRng(rng));
-            const expected_g1_sx = curve.G1.toAffine(curve.G1.timesScalar(expected_g1_s, expected_prvKey));
+            const expected_g1_sx = curve.G1.toAffine(curve.G1.timesFr(expected_g1_s, expected_prvKey));
             if (curve.G1.eq(expected_g1_s, c.delta.g1_s) !== true) {
                 console.log(`INVALID(${i}): Key of the beacon does not match. g1_s `);
                 return false;
@@ -288,7 +287,7 @@ module.exports  = async function phase2verify(r1csFileName, pTauFileName, zkeyFi
         // Works*2   const first = curve.Fr.neg(curve.Fr.e(2));
         const first = curve.Fr.neg(curve.Fr.e(2));
         // const inc = curve.Fr.inv(curve.PFr.w[zkey.power+1]);
-        const inc = curve.PFr.w[zkey.power+1];
+        const inc = curve.Fr.w[zkey.power+1];
         buff_r = await curve.Fr.batchApplyKey(buff_r, first, inc);
         buff_r = await curve.Fr.fft(buff_r);
         buff_r = await curve.Fr.batchFromMontgomery(buff_r);
@@ -317,7 +316,7 @@ module.exports  = async function phase2verify(r1csFileName, pTauFileName, zkeyFi
     async function batchSubstract(buff1, buff2) {
         const sG = curve.G1.F.n8*2;
         const nPoints = buff1.byteLength / sG;
-        const concurrency= curve.engine.concurrency;
+        const concurrency= curve.tm.concurrency;
         const nPointsPerThread = Math.floor(nPoints / concurrency);
         const opPromises = [];
         for (let i=0; i<concurrency; i++) {
@@ -374,7 +373,7 @@ module.exports  = async function phase2verify(r1csFileName, pTauFileName, zkeyFi
         ]});
         task.push({cmd: "GET", out: 0, var: 2, len: nPoints*sG1});
 
-        const res = await curve.engine.queueAction(task);
+        const res = await curve.tm.queueAction(task);
 
         return res;
     }