Casting bar hooked to mouse-curser; possible?

[Prisma]

I tought about programming a small casting bar that is hooked to the mouse-curser.

The only thing that I've done so far are Boss scripts for my guild and some other simple lua stuff, so I don't have any experience with the XML part of the interface scripting. That's why I wanted to ask if something like this is possible.

In some addons you can 'drag' stuff around, so while the mouse button is pressed it's kind of hooked to the mouse, however this is often pretty chucky, and most likely too chucky for my purposes. Is there any way this could be done smoother?

I'd like to know this before I start digging into XML and realizing that I can't achieve my goal anyway.

Ok, I'm terribly sorry. I just realised that this should have been posted in the developers section of the forum
Whould be glad if it could be moved