Helping another user with a similar issue, they resolved it by un-checking the “Support Metal” box here (Project Settings>Engine>Cooker):
(If unchecked, try checking it. There may be a bug with this feature.)
Regarding your blank project log:
MainFrameActions: Packaging (iOS): IPhonePackager: IPP ERROR: Application exception: System.Security.Cryptography.CryptographicException: El conjunto de claves no existe
MainFrameActions: Packaging (iOS): IPhonePackager:
MainFrameActions: Packaging (iOS): IPhonePackager: en System.Security.Cryptography.Pkcs.PkcsUtils.CreateSignerEncodeInfo(CmsSigner signer, Boolean silent)
MainFrameActions: Packaging (iOS): IPhonePackager: en System.Security.Cryptography.Pkcs.SignedCms.Sign(CmsSigner signer, Boolean silent)
MainFrameActions: Packaging (iOS): IPhonePackager: en System.Security.Cryptography.Pkcs.SignedCms.ComputeSignature(CmsSigner signer, Boolean silent)
MainFrameActions: Packaging (iOS): IPhonePackager: en MachObjectHandling.CodeDirectorySignatureBlob.SignCodeDirectory(X509Certificate2 SigningCert, DateTime SigningTime, CodeDirectoryBlob CodeDirectory) en d:\Build\++UE4+Release-4.12+Full\Sync\Engine\Source\Programs\IOS\iPhonePackager\MachObjects.cs:l?nea 2085
This appears to be a Provisions/Certification issue and not related to your project issue.