It seems there's a major bug that ties too many things to the range sliders or something. Things like CVs not being visible, not seeing acks and GVs and anything that you normally should.
I think whatever this huge bug is, it's screwing your graphics over. Lag in hat switch means it's trying to process too much. crash on hat switch = something not right.
Hopefully, for my FPS' sake, it'll get fixed in the next patch.