Well, I have a 2004, Mehran LE CNG. And the AC works fine. Till last summer the temp. was kind of ok (around 65-70% in traffic and used to be 50% on open roads; when running on CNG, with petrol it goes down).
And when you say "MHUJE BATHO KAY MEIN AC LAGWAOO YA NAHI" well brother we are running a petrol eng. on CNG so why not put little more burden on this little 800 cc thing i think it will survive.
Go ahead get it fixed.
(Ummm by the way this coming summer, Im planning to take out the water stoper of my Mehran, to bring down the temp.)