I am not sure if it's related but when adding a hair system I get "Export failed, check script editor for details" when starting Fire. Script editor shows "Warning: Maxwell Interactive Viewport: scene export canceled."
This is strange. I can no longer use any of these features on any versions of beta plugins. It seem the reason is not a plugin but a new Maxwell Render version 3.1.99.11
When I reinstalled an earlier version (3.1.99.10), everything started to work again, it's no a plugin's fault. I'll have to post in another forum.
This usually happens between engine builds. The extensions API has changed, so the older plug-in cannot load extensions compiled with the newer API. I'll upload an updated plug-in today.