Hello there!
Today stumbled upon a particular issue where I sent a Rig to the animator and Maya couldn’t find a certain node type. This causes whole joint structure to collapse making the geometry invisible unless you unbind it.
The Animator I work with had just solvers installed from this package:
(It was working with 3.6.0 and every version before that).
So we decided to install a new version on top of existing one.
Apparently upon installing newest version (3.7.9) Maya made additional tab in Plugin Window and didn’t load them. So it was loading the old ones from the previous version upon opening Rigs from 3.7.9.
So after I unloaded plugins from here
and activated them there
everything was finally working.
I’m not sure if it’s caused by the installation method or by the version that package has, but it can be fixed by uninstalling all mGear related plugins from a machine and installing the correct version.
This is pretty much a workaround I found by the issue I might have made by myself, but just putting it here in case someone faces the same issue 
Cheers!
