Hi jaffasplaffa,
Yes, the copy shortcut should work, and doesn't. That's what my recent patch fixes, and it's been merged into the main repository, but it's up to johannes when it will be released as a precanned package.
As lokki says, the acceptance of letters is new, because it's part of a new, useful feature. "c" is accepted, because it is necessary for the entry of musical notes. You can only write meaningful letters into the dial, though it's up to you to enter them in a meaningful way. Try some of the examples I gave to see what it does - it's highly beneficial to almost every object.
Lisa