I am currently trying Mutaflor as well and so far it seems to increase my UC pain a little (just a little) bit and slightly increase gas-- I may try taking it on alternate days for a bit, then one cap a day, and slowly work up to the recc dose of two caps a day. In the meantime I take a lot of VSL-3 as it is, but want to give Mutaflor a good try since its ingredient - non-pathogenic e-coli- is unique. All strong probiotics may take some adjustment time.
PS on the definition of sharting- if you don't mind hearing graphic language here is a clip from a Ben Stiller flick for a quick laugh... provided it doesn't make you shart...
http://www.youtube.com/watch?v=NiNZdTSH3-A