I've never experienced any side effects with Creon. But then again my GI symptoms are so severe that not taking it is awful, so I'm not sure I'd be able to note a side effect. Like Ank said, dosing does depend on what you ate. I need more with high fat and/or high protein meals. It will take some trial and error to figure out the exact right dose so that everything is getting digested well. The nice thing for me is that I get pretty compelling feedback within a day, so it is easy to learn from my errors.
It seems like there is a lot of fuss about when you take your pills (right before, during, right after a meal/snack or some complicated combination of the three), but as long as I'm within a reasonable proximity of the meal they seem to be beneficial. Consistency so that you remember to take them is probably more important that the exact moment they are imbibed. I never take them more than 10 minutes before a meal, but if I have forgotten to take them, I've taken them 30-45 minutes after a meal, which isn't ideal but better than skipping.