andredr, I'm not a proper substitute for TDW, but I can give you a quick answer to your first question: I presume you know how to use the options file editor for New_UIs (If not, go here:
http://www.subsim.com/radioroom/showthread.php?t=199708) Under the Heading tab, you will find the hotkey assignment for the heading dial. Double-click on the subhead "Hotkey" and you will get a dialog box allowing you to change the assignment. You'll have to reactivate the mod using JSGME after you make the change.