I have a bigger belly than you do ozone...much bigger.

Find myself going through a routine proceedure. First I put the belt on and snug it up. Then I add the sporran strap. After the sporran strap is on I find that the belt is way too loose and I snug it up. Sort of like cinching up a saddle on a horse...a two move effort. Maybe its my body adjusting.

I get them wrinkles on my casual kilts so just pull each side of the apron at the same time and it goes away.

For what its worth, I've gone to using the side buckles on the kilts I own that have them, leaving off the belt, and just wearing a sporran...or a vest in lieu of a sporran.

My kilts are a lot more comfy WITHOUT a belt...course that's because of my belly size...but suspect they are for trimmer guys too.

Ron