I downloaded this ages back, looked at it and removed it. Not so long ago after hearing loads of good things about it, I downloaded it again, looked at it and removed it.
I'll admit that I can't really figure out what it's meant to do, but when you play a healer you're already mostly focused on a small area of the screen. I don't want to be consigned to spending all my time staring at a load of coloured squares with smaller coloured debuff squares appearing on it. Seems to take a lot of the joy out of what is already a fairly niche gameplay experience (healing).
Then get Xperl. I personally use Xperl despite acknowledging I'd probably be a little quicker with Grid.
Basically Xperl is a set of fully customisable raid frames. You can put your own frame, target frame, focus, party and raid frames wherever you want. You can choose the size and what information they display.
ie - You can set Xperl to show % health, or health deficit. I use the deficit as I then know what heal to use more easily.
If you get Clique, that allows you to set up mouse and keyboard binds for spells which work on whichever frames you want to. Just the raid ones, the party ones, your own or everything etc.
For my pally (iirc) I had.....
Left Click - Flash of Light
Right Click - Holy Light Rank 11
Shift Left Click - BoP
Shift Right Click - Holy Light Rank 9
Middle Button - Divine Intervention
Alf Left Click - Cleanse
Alt Right Click - Blessing Of Freedom
Button 4 - Holy Light Rank 7
Button 5 - Holy Light Rank 1