Well, i haven't gotten any EXP since the beggining and i use /gamemode 1 to give me some if i need. Here's a video of me killing a mob on BouleField, and after that in a world i made -Quote from Preistbob
You definitely should be getting xp, while playtesting it xp was given and could be used.
P.S. Love the Level 2 ride D: , i hope it gets done soon because the map is incredible.