I recently released an update for Polymorph on 1.18.x which still had its own AE2 and RS integration and I had a chance to look into the issue with the button shifting incorrectly when the screen or GUI was resized. This is the commit:
illusivesoulworks/polymorph@2d8be10

I believe something similar, if not exactly the same, could be used to solve this same issue on these add-ons. It essentially involves checking for changes in height and then refreshing both the output slot and widgets accordingly.

Sounds great. I'll throw these in when I get the chance.