Re: how to map CTRL with none-letter keys

You don't mention whether you're using Vim in a terminal or GVim. In a
terminal, this is generally not possible, because typically, terminals
can only receive Ctrl key combinations which have a corresponding ASCII
control character, and none of the characters you listed do.

In GVim, I don't see why this wouldn't work, but I don't use GVim much
so maybe there's an issue I'm overlooking.