I posted about this in the asp.net section, as I figured it's a IIS problem. But I spoke too fast when claiming I solved it.

Swapped Apache with IIS, and got it working.

Just seems when I edit my PHP code (local wordpress theme), I have to refresh / hard refresh several times before the change show up.
Weird thing, it's PHP output that seems to get "cached".

Dunno anything about this, so any help would be appreciated