EDIT. I see that you extended your post
in OS9 you need CW 5.x (rather than 7.x) and the VST SDK 2.0 or 2.1
Ok, got it. MPW not any good?
you eventually also need to know the differences between VST 2.1 and VST 2.3
I have no idea, honestly.
then you need a person or company who registered for VST2 early enough to still be allowed to publish those, because we may not do that otherwise.
Grey zone? But I can do it in my bedroom, right?
(I did compile AU VST wrapper for my needs using 2.4 SDK some time ago)
he seems to have a custom template for his plugs, you might want to look in that stuff under XCode.
I'll take a look. But I have no idea how to translate that to OS9/CW/MPW.
if something is UB, stripping off the intel stuff should be simple (that´s what i heard )
Piece of cake. I do it almost daily. lipo or ditto command line tools.
BUT, the question was about compiling for OS9. C++ is C++, no?