I am planning to use threshold cryptography in a Java application. So far, I have only found ThresSig and a ECDSA implementation used in TwoFactorBtcWallet. However, ThresSig is based on a 15-years old scheme, Shoup's Practical Threshold Signatures, and I can't figure out how to re-use the aforementioned ECDSA implementation for my own needs (I am not even sure if the code supports more than 2 parties).
Are Shoup's Practical Threshold Signatures considered secure nowadays? Are there any well-known pitfalls or recommendation on sizes, etc.? If not, is ECDSA an appropriate building block and how?