Quick test with superkiller (uses UPX) shows that packed executables work without any special measures.
Removed FindWindowA from list of calls to hook.

Prototype I had this (according to comments in the source) for
superkiller support, but superkiller can set the console title
perfectly, so I wouldn't know why I should hook FindWindowA in addition.
Possibly this was some hack in superkiller to set the console window
title on older windows versions (MSDN states SetConsoleTitle is
supported from Windows 2000 on).
emulation: intercept ShowCursor.