Mmmm. We put in a fix for this in Patch 2.1. 

I can't make the bar disappear at all anymore and when the scroll button is missing all my units are visible in the panel (although the last one at 80% scaling does indeed hang over the edge a little but it's still visible and usable (not enough of a problem for me to try and get code resource back to fix it)

Are you sure you have more unit types than the panel supports?

Had a look over this. It could be a bad install on either yourself or your friends pc. The error message is indicating a core piece of code doesn't exist.

We've released a new patch, maybe just try a reinstall and see if that helps.

Our code team had a look into the crash. Unfortunately the responsible code is part of the Unity Engine's code and not our own. There's no solution in the current version of the engine. If we ever update again (unlikely due to dependencies) then it my end up resolved.