Microtonic often (not always) does not load in bitwig or it takes a very long time (like minutes..). I contacted bitwig but they stated this is a plugin issue. Currently I'm running bitwig 2.3.5
microtonic 3.2
Osx 10.13.6
The message in bitwig
createAEffectinstance returned NULL

I tried to debug this but it was very hard because of how Bitwig runs plug-ins in a separate process (by default). From my logs it looks like Microtonic never gets a chance to perform a proper cleanup when it is removed from a project. That would explain why it has problems loading next time (the old one still holds a system-global lock on it's preference data).

Turning off the plug-in isolation feature solves it for me. Like this:

I'll contact Bitwig and ask them to take a look at what they are doing when plug-ins are dropped. I can't remember this being an issue in earlier Bitwig versions. But I might be wrong.