Is it still overheating? I wouldnt jump to conclusions just yet, a little milky residue under the cap is normal for some cars due to condensation.

Is your exhaust white or smell sweet? Is there clearly water in your oil?, like on your dipstick, are you losing any coolant? Is there oil in your coolant? Did you bleed it correctly? Bleeding it can take a couple trys.

I would say the hardest thing to doing the head for a newbie is getting all the timing set up right. You cant make any mistakes on an interference engine.