function start() {
  $('.btn-startInjection')[0].disabled = true;
  document.getElementById("p-error").innerHTML = '';
  loadFiles().then(data => {
    let dsiware = data[0];
    let movable = data[1];
    let game = data[2];
    let save = data[3];
    let ctcert = data[4];

    /* Validation */
    if (movable.length !== 0x140 && movable.length !== 0x120) throw new Error('movable.sed size not valid');
    if (ctcert.length !== 0x19E) throw new Error('ctcert.bin not valid');

    let crcGame = getCrc(game);
    if (!constants.hashes.srl.includes(crcGame)) throw new Error('game_XXX.app is not valid');
    let crcSave = getCrc(save);
    if (!constants.hashes.save.includes(crcSave)) throw new Error('public_XXX.sav is not valid');

    /* Data Extraction */
    let locC = constants.dataLocations.ctcert;
    let publicKeyR = sliceArr(ctcert, locC.publicKeyR.off, locC.publicKeyR.len);
    let publicKeyS = sliceArr(ctcert, locC.publicKeyS.off, locC.publicKeyS.len);
    let privateKey = sliceArr(ctcert, locC.privateKey.off, locC.privateKey.len);

    let locM = constants.dataLocations.movable;
    let movableKeyY = sliceArr(movable, locM.keyY.off, locM.keyY.len);
    let normalKey = extractNormalKey(movableKeyY, constants.keys.keyX);
    let dsiwareData = extractDsiware(dsiware, normalKey);
    if (!dsiwareData) throw new Error('DSiWare.bin can not be decrypted with the provided movable.sed');

    /* Game & Region checks */
    validateDsiwareRegion(dsiwareData, game, crcGame, crcSave);

    /* msed_data extraction */
    let msedDataHex = extractMsedData(movable);
    let movableCrc = getCrc(movable);

    /* app replacing */
    let srl = dsiwareData.other['srl.nds'];
    if (game.length > srl.length) throw new Error('Game not compatible');
    let end = sliceArr(srl, game.length, srl.length - game.length);
    let newApp = new Uint8Array(game.length + end.length);
    newApp.set(game);
    newApp.set(end, game.length);

    /* sav replacing */
    let sav = dsiwareData.other['public.sav'];
    if (save.length > sav.length) throw new Error('Save not compatible with this game');
    end = sliceArr(sav, save.length, sav.length - save.length);
    let newSav = new Uint8Array(save.length + end.length);
    newSav.set(save);
    newSav.set(end, save.length);

    /* update data */
    dsiwareData.other['srl.nds'] = newApp;
    dsiwareData.other['public.sav'] = newSav;

    /* update footer hashes & add ctcert/pubkey */
    dsiwareData = rebuildFooter(dsiwareData, ctcert);

    /* signing */
    let body = {
      publicKeyR: byteArrToHexStr(publicKeyR),
      publicKeyS: byteArrToHexStr(publicKeyS),
      privateKey: byteArrToHexStr(privateKey),
      hashesBlock: byteArrToHexStr(sha256.array(dsiwareData.hashesBlock)),
      apcert: byteArrToHexStr(sha256.array(dsiwareData.apcert)),
      msedDataHex: msedDataHex,
      movableCrc: movableCrc,
    };

    dsiwareData.dsiwareLength = dsiware.length;
    dsiwareData.keys = {
      movableKeyY: movableKeyY,
      normalKey: normalKey,
    };

    /* Signing */
    return signData(body, dsiwareData);
  }).then(sigData => {
    let { sigHashesBlock, sigApcert } = sigData.signatures;
    let dsiwareData = sigData.dsiwareData;

    sigHashesBlock = parseHexString(sigHashesBlock);
    sigApcert = parseHexString(sigApcert);

    /* inject signatures */
    dsiwareData = injectSignatures(dsiwareData, sigHashesBlock, sigApcert);

    /* rebuild dsiware */
    let dsiwareFinal = buildDsiware(dsiwareData, dsiwareData.dsiwareLength);

    /* offer file to download */
    download(dsiwareFinal);

    /* End */
    console.log('Done');
    $('.btn-startInjection')[0].disabled = false;
  }).catch(error => {
    abort(error.message || error);
  });
}