Seems that the keyboard shortcut minimizes P2A but will not restore it.  A mouse button shortcut works just fine minimizing and restoring the P2A window.

This is likely due to having the "Require P2A or SIM Focus" option turned on.  If so, and P2A is minimized, you would have to have the focus on the SIM in order for the that HotKey or Button to work.  Your solution would seem to be a good alternative.

Dave