Do not bother using Gravity on Maat, he will resist pretty much 100% of the time XD(you should rely more on Sleep2 than Bind on Maat, i forgot which but he outright resist 100% on either bind or gravity during my fight) . :Edit:
When you go in, IMMEDIATELY RUN to maat do not waste time, once you see him Sleep him... The longer you wait to sleep him, the more buff he's gonna put on him.
Put on Blink, Stoneskin, Refresh then Dispel. Nuke or Rest when needed... Then Sleep2 again, rest for bit, recheck buff/renew buff, nuke, Sleep2 rinse repeat.
If you have Meds, at around 50% Maat, go Chainspell then Nuke nuke (sleep him if he use Nuke etcetc) As long you have max skill in enfeeble and elemental .. you should be fine.. if not, go skill those 2 up...
Oh and in my opinion, Pro and Shell is useless with Maat RDM, why? Well, the point is you don't want to let him touch you at all in the first place

... At least he didn't touch me once when i fight him, apart from getting blinded by his Blind.. >
One more thing, if you want some practice, try to look for people that is doing Bastok Mission9-1, that NM is pretty fun for RDM to solo, and pretty good for RDM to practice (and ego boost)
PS: we demand more pics.