I have tried to make a test rig using the default proxy mesh generated during the Rigging Tools Plugin Wizard, but it always hangs at 50% during the “Build Control Rig” step and fails right after taking the thumbnail image of the rig.
I have tried the plugin in both Maya 2013 and Maya 2014 with the same results. I have also tried removing Read-Only rights in the rigging tools folder, as well as creating a copy of the rigging tools folder on my C:\ drive and pointing the plugin to that. Also, grabbed the latest preview build and the rigging tools folder there with the same results.
It looks to be saving out a .mb file of the scene right before any control rig is built in the proper Projects folder:
It then looks to actually be building the control rig, but once the progress gets to 50% and hangs, I can see an error flash by in the help/message box and Maya loads a new empty scene.
The only error lines I could find in the script editor are:
Error: RuntimeError: file D:/UE4 Rigging Tools/MayaTools/General/Scripts\ART_autoRigger.py line 9265: setAttr: The attribute ‘driver_upperarm_l.rotateZ’ is locked or connected and cannot be modified.
Attached is the entire script editor log.