I am experiencing an issue in Maya 2015 with the latest plugin (2.22.2 - 7.0):
1. Start Maya without Octane loaded.
2. Create geometry or (load a scene that wasn't saved with Octane loaded).
3. Load Octane plugin.
The geometry nodes get populated with "nonsense" values in the Octane-specific attributes (see picture). For example, "Octane: Geometry type" should be "Global," "Movable proxy," "Reshapeable proxy", etc., but instead it's populated with some large integer. If I try to render with this, Maya hangs and seems to suck up more and more RAM until the system freezes.
This does not happen for me in Maya 2014. I don't know if it happens in other versions. Or maybe if it's due to certain 3rd-party plugins (although I'm pretty sure I have the same plugins loaded for both versions, except Xgen and Bifrost of course).
My current workaround is to load in 2014, activate Octane, save, then load in 2015. But this probably won't work for all scenes.
