I am having this same issue but for Composer pro 3.2.4, it wont even open. if i open task manager and watch that as i try to open composer the ComposerPro.exe shows up in background process for a second then disappears. I've tried uninstalling it, restarting my computer and downloading and installing like 5 times. i just found out that composer pro Os 2.10 and down all open and work just fine, it's just Os 3 that stopped working. is there anything Control4 tech support has said about this?