Cool, now I got it. Yeah, I had these issues a couple of times but was hoping that they are fixed by now. I'll try to figure out what's wrong.
As for material picker, I need more details, but I think I know where is the issue.
So let's assume you have some geometry in a group and you have some material. Material is being applied to the group but not the geometry inside the group, right?
So when you try to pick material from the group, it works (because you pick the material from the group). Then when you open the group and edit the actual geometry which has no material and you try to pick material from a face, picker doesn't work.. right? If so, I can see why.. faces have no material applied so it doesn't work.
I never thought about this scenario.. Plugin logic works perfectly
I'll check this and will try to implement a workaround.
Thanks for pointing this out.
PS: English corrector? Never heard of it. Only raw poor English knowledge, only hardcore