I built my first trainer, and the right aileron is slightly lower (1/16"-1/8") with the servo centered.. it flys alright, but always wants to roll very slow, couldnt trim it enough to fly strait and level...

You could twist it back into position and use a heat gun or a covering iron on it to take the twist out of it... you may have to remove the aileron to do this. On the other hand, you could leave it alone... like stated above... it may not make any diffrence.

Welcome to the hobby