Hi @fwilleke80, I'm using 11.3 and I've no issue on running the plugin BigSur.
With regard having the code running on your customers' machine I think you need to notarise (is it what you mean by sign my plugins?) the plugins before giving them otherwise the security mechanism found in BigSur might easily have block them.
He has answered the usual security question that macOS shows him (as I don't sign my plugins yet), but no success.
- Can you ask your customer what "usual" security questions he answered?
- Can you ask your customer before unpacking the zip archive, that maybe he has downloaded from an email or a website, to run
$ xattr -d "com.apple.quarantine <zip archive to your plugin>"