Looks promising! Good find!
Metro Pcs is a carrier, like att, verizon, sprint, boost mobil ect....it might be a problem with the flash of the ROM I'm not sure what Metro PCS is (i also never really used cm7 alot either) but i can tell you that just the other day i was having problems with mms using reborn rom and a dirty flash fixed it up maybe its worth trying that or even a whole clean flash
I know how to fix MMS and data if you need help...I am running my optimus v on metropcs.
Edit: My optimus V is running Optimus S firmware and is on metropcs still.