So if I try to change the custom background for my character, it refuses to show up on my character sheet. Like, if I change it from 2 skills and 2 languages, to 2 skills and 2 tools, those skills won’t even register. They won’t pop up in the options for expertise, they’ll still be an option on the skilled feat for example, the character sheet won’t acknowledge they even exist. I’ve tried closing the website, refreshing, I’ve tried going back to the original configuration, you have to delete the character sheet and start over. Otherwise custom backgrounds won’t work for that character ever again 

Same, I just try it now, it doesn't work

Switching back to a prebuilt background, then switching back to Custom and *clicking Save* under Customize seems to fix it. Though it might take doing this a few times.

I've experienced this on one of my characters, and one of my players in my campaign have had this issue also.  We were able to get my player squared away, but my character still has this problem.

I am also experiencing this issue, resetting between other backgrounds has not helped fix the problem.