I've just pushed out an update containing a little fix to the XP system. It would seem there was an issue related to Custom Mode that could cause your XP to completely reset, and I think I've fixed that now. I think :)
Apologies if you were affected by that!
As always, if you have any feedback or encounter any problems, please do not hesitate to let me know. And feel free to come and say hello on the Wrongworld Discord, although I haven't found much time recently to get on there myself!