Hi Chalecampb,
Sorry for your tech issues – it’s always a pain in the butt when computers go rogue and try and ruin your day.
As for the lag issues, here are some things you can do to speed it up.
– hide parts you don’t need to see
– disable the subsurfs
– disable the surface deform modifier on the leg guards (this will eat up the speed on an old machine)
– change to solid view (not any of the material views)
As for the weird weight painting issues, I’m not sure I follow along 100% with what’s happening.
It sounds like it may be a bug, but could you screen record the issue.
This will help better diagnose what’s going on.
cheers