While my gut is not too bad right now, I understand the sporran bunching. I think one of the main tricks it too wear the kilt at the right height (on the gut) and let the sporran find it's place by trying different holes in the belt. You will find the spot that is natural and looks best. I think the worst thing to do is to wear a traditional style kilt under the gut! This makes the kilt look bad, uneven, unbalanced, and may cause the kilt to bunch up too. The sporran will never fit right if the kilt is already bunched up.