The Improbox licence key is bulletproof. You don't have to delete it nor do you have to uninstall the tap... just move it from Auto Start to Program Files. There is nothing wrong with the ICE file manager (in that regard)... you can't delete the licence key with anything and it is designed to be that way.
Improbox is completely and comprehensively configurable. If you go to the Improbox menu you can configure it to NOT use the 0 key. From memory, by default, it uses the 0 key to jump to the start of a recorded file.
Regards,
Rob