Rip off lame game
Not sure what "glu credits" are, but you need to direct your inquiry to the entity that promised them to you. If it was Castle Clash / IGG then you can use the link in game for Live Support / Chat. However if it was a "Tapjoy" sponsored event you need to speak to "Tapjoy".
Follow IGG @Facebook.com/IGG Follow CC @Facebook.com/CastleClash
Sounds like downloading CC was supposed to give him some kind of credit, similar to Tapjoy.
You are better off complaining to Glu.
While you do, why don't you give CC another shot. You might find it's only a half the rip off and half the lameness than you think!