Hmm... So no clue what the console log error you are showing has to do with my plugin
...However here ya go, I do have a fix for this...
Sorry it took so long for me to check further into this. Simple fix really.
Updated to v2.20 Re-Download and add the following script after your message/choice/etc. window is closed.
The problem was pretty simple... once the choice window is closed the game doesn't know to refresh and reactivate the skill window. So we have to tell it to. I may work an "auto-fix" into my menu-on-map system soon but for now just use that function to return and refresh the window after choice options, etc.
Seems to work nicely for me

Updated
menu-on-map itch.io page to show this feature in use now