Thanks! You're right that it feels weird on the underside of platforms, though you get used to it ;-). We considered some alternatives (if you jump on to the bottom of a platform then invert the controls until you let go), but they were just weird in different ways.
The feedback button does hide the window. Perhaps it shouldn't. I'll fix it :-)
The feedback button does hide the window. Perhaps it shouldn't. I'll fix it :-)