ORIGINAL: HollywoodHitman
This plane was my first ARF after my trainer. I'm no expert, but my Pulse is similar, I did nothing but glue 'em in and it flies like a dream. I wouldn't sweat it.
Yours had a pretty large gap like this? Did you try and squeeze the gap tight when you glued it?
On mine,it is definitely the ailerons. I put a straightedge to them and they are curved. The wing TE isn't perfectly straight either,but I think the majority of the curve is the aileron itself.