The good news is that there shouldn't be any difference between an older version of the InstallRig plugin and the most recently posted version, Sebastian. So, using the old one you have would be fine.
I don't have a Mac, so I can't check that version of the plugin...if someone else on a Mac could confirm the problem, and one that we know works gets posted, I'll replace the one in the released version of the rig. I hope that made sense.
mac test
placing the install rig in the the .hxt folder crashes AM
even if i remove all of the other hxt's
mac snow leopard 15.oh