I don’t know if you have found this little gem on internet, but it’s worth checking: 4Front Rhodes 2.0 have some problems displaying interface in Renoise. I have tried with other AU and VST hosts, and it looks just fine in them. Problem happens only with AudioUnit version of a plugin in Renoise. Please, have a look:
Horizontal controls are below sliders, so it’s quite hard to work with them. It looks like overlay is misplaced, but plugin functions itself. Running it on Snow Leopard 10.6.5 and macbook 3.1.