I just picked up Renoise last month and recently decided to also buy Z3ta+ 2 (2.1.1) for it. I’m running on a Mac (10.8.3), and Cakewalk provides a VST 3 (which Renoise doesn’t recognize) and an Audio Unit plugin (which I’m using). When I open the plugin window (pressing Ext. Editor) for the first time, everything works great. But if I close the window (either by clicking on the OS X close button or the Renoise Ext. Editor button) and then open it again in the same session the window is blank. See attached. I’ve tried this on Renoise 32 and 64 bit with the same effect. The window stays blank upon repeated summonings. I can fix the display by reloading the song, or by changing the instrument from Z3ta to something and then back again, or by restarting Renoise. Creating a second Z3ta instrument results in THAT window showing correctly, but I’d guess that’s because it’s a separate process. I have a trial version of Reaper so I tried loading the AU plugin with that, and it had no problems.
I had this window-blanking problem during the Z3ta trial period too, but I assumed it was a buggy nag screen popup obscuring the display and didn’t worry about it then. Perhaps there’s a cache somewhere I need to kill? Messing with the plugin options doesn’t seem to ameliorate the issue. No other plugin I’ve tried has this issue.
Is any other plugin VST or are there also AU plugins among them?
I know some AU editions have more complications.
I’m not sure if this problem is really AU specific though, but as you stated, the VST version is a VST V3 that you can’t test in Renoise.