I might be jumping the gun on this since I haven't doublechecked, but it appears that the hotkeys are in the noclose.ini file.
I don't use the hotkeys, so I assume these two lines from noclose.ini are the default hotkeys:
this is an AutoHotkey script, so these are AutoHotkey key notations. Check AutoHotkey help for the key notations for the keys you want to use. Then edit noclose.ini with a text editor like Notepad.