@zipit This plug-in has a twin plug-in that has some properties with the same name, and I suspect that the properties with the same name cause conflicts (even if the ids are different).I made the modification and it is normal now. Thank you for your reply Cheers

Hi sean, thanks for reaching out us. The broken forward compatibility between R20 and R21 is reported on Changes in R21. With regard to backward binary compatibility, it has never been possible to run a plugin built against a more recent API and load on a previous Cinema 4D executable as reported on Portability and Compatibility. Best, R.

Just FYI: you find that information regarding ./res/libs/win64 in the documentation: Development for Microsoft Window

@m_magalhaes Hello, thank you very much for your inspiration. You've been very helpful. There is no need to overwrite TranslateDescID(), only two macros HandleDescGetVector and HandleDescSetVector can realize my idea. Thanks again! Cheers, Sean

@m_adam Thank you. Thank you very much！