Thinking about first flight...

[Michael Burbidge]

Either my right aileron or right flap is slightly twisted. The flap and aileron trailing edges are off by 1/8 inch with everything else rigged correctly. Is this enough to cause any serious control issues?

Thanks,
Michael

[JonJay]

None. Although you should know which one has the twist. Easy to check with a long straight edge.

[Mike S]

Does it fly straight??

[PCHunt]

From the title of the OP, I am guessing he hasn't flown yet.

[Smilin' Jack]

Michael.
I would start at the tips again and assuming you have the ailerons aligned with the machining holes even the ailerons up then work your way to the flaps. You can also put a big wood clamp on the aileron and the tip to hold one side.

When you get to the flaps. get a dial angle and set it on the flap at a rivet line. You'll be able to tell which flap is off.. you might have to adjust one up a turn or down. Not a biggie.
Jack