I would say that yes the flashes should both be at the outside, also you should make sure that you center the belt and sporran on the kilt, one good thing about quite a few tartans is that they have a line going through the middle making it easy to do,than hike the kilt up to your natural waist so that the bottom hits just above your kneeto the middle of your knee.
I also think that the sporran is a wee bit high, you should have a gap of 3 or 4 fingers between the belt and the sporran. I know it sounds like alot of stuff but really it is just a mater of polishing up just a wee bit more.

I was also thinking you might want to look at this post about a wedding where the groomsmen were dresssed similar to what you have:
http://www.xmarksthescot.com/forum/s...ad.php?t=27680