Hi there! I think I see the problem here - I wanted to save time on the eligible couple check (which runs when two sims interact for the first time in a session, so all of these times add up), so instead of taking the time to calculate their relationship it'll just ban romance if at least one is a child or younger. That wouldn't be possible in the vanilla game, and I didn't consider mods allowing romance between children, so mine will conflict there... if you do want to remove it for the time being, make sure you keep any .cfg (settings) and .json (relation storage) files so you don't lose data and won't need to do any setup to re-add the mod in your game.
I've been working on making the eligible couple check faster, so I'll hopefully be able to remove this limitation in the next update without lagging everyone's game - I can't guarantee when it'll be out sadly, hoping within the next month or when it breaks and I have to fix it, whichever's first