I'm currently going pretty much vanilla, since I started having a bunch of issues with a number of skins not working with each other. Or with the newest update. =/ So yar. No skins atm really.
they look nice, but I won't use them either because neither look better than what it is currently IMO. And Captain Ashton, if you don't use skins then how do you tell whats happening? :O Everything would just be grey!!!
What I'm saying is that custom skins don't slow down your game any more than the regular stock ones, custom models might if they are made improperly, but custom skins do not.
The link I posted for the lightmaps neither crashes my game nor slows it down from what I can tell. And I have a few year's old hardware, too. May be some other issue causing the crash?