I joined a group playing RotRL Anniversary Edition, and they sprung a couple rules I can't really find basis for anywhere. The biggest of which is that moving through allies in combat is considered difficult terrain. I've been playing Pathfinder for at least five years (PFS, mostly) and have NEVER seen this done before. The only basis I can think of is them misinterpreting rules for crowds...
The second one is that a diagonal counts as moving through all four squares (the one you are moving to, and the ones next to it). Never seen this rule, either, but the situation comes up less.
Is there any support for these? Or, even better, is there support that these interpretations of the rules are wrong? I would very much like to never have to worry about this again, it's a very frustrating thing to deal with in combat.