does KMR cause loose stools??

I fed my kitten Jake (5 weeks old) with KMR only yesterday because he seems to prefer it to kitten canned food. This morning he had diarrhea, well I don't know exactly what the definition of diarrhea is but his stool was kind of watery. I decided that it might be from the KMR so I fed him with only canned food this morning, and tonight his stool is not watery anymore...But he doesn't really like the canned food and at 5 weeks I think he still might need the KMR. Maybe I need to control the amount that I am feeding him. Can someone help me with how much I should give him and how often?? I think I read that KMR could cause diarrhea if portions are increased from day to day, and I gave him a bowl full for him to eat whenever he pleases because I was afraid he would be underfed...

Yes - the KMR can do that. Changing his food around suddenly can, too.

Two things I suggest. One - mix the KMR with the wet so its mush and let him eat that. Second - you can get probiotics from the vet or at the pet store that will help with any issues he might be having in digesting his food.