[bojan]

Hmm
Balance does not have to be absolutely perfect, just a bit unbalance is allowed, but the mount should work AGAINST this unbanlace (or, tendency towards unbalance).
Did you have some wind while imaging?

Important thing is, you should not see (or feel) any free movement of the axes, apart from obvious freedom of movement that is expected.. not too tight, however you should feel viscosity of lubricant when moving the mount around axes..