AvaStar users have Gaia Clary’s survival kit for Fitted Mesh. Now Astrid Kaufmat has put a survival kit for Maya users up in the SL Forum. See: Maya Survival Kit (for fitted mesh).

Neither Gaia not Astrid are claiming these kits are the end-all-be-all solution for working with Fitted Mesh. But, they will help you survive the current state of affairs.
Astrid recommends getting the plugin ngskintools, which you can download from here. She links to guides and tutorials for using the plugin in her post, link at top.
Astrid’s basic work flow is to weight to the mBones as Maya users have prior to Fitted Mesh. Then copy the weights to the collision bones we have now. She uses a script named abweightlift, which can be downloaded from the creativecrash site. Her post explains how to use it.

