Yep, you're totally right there, same thing happens on my machine. Looks like I accidently introduced a dependancy on Redle Mansion UI mod, I'll fix this dependancy in my next release.
In the meantime you can fix it on your local version by opening up the file
mods\ChastityBelt\scripts\Mansion.gd
and commenting out line 73 by adding the # symbol infront of it
e.g. replace the text
nav_node.hide()
with:
#nav_node.hide()
Once you made this edit, you can apply the fix to the game itself by going back into the in game mods menu from the main menu and clicking "Apply" again.