The change fee is $50 normally I think and waived for MVP Gold. I was only MVP last year and they waived it for me many times also.
I have had problems using the Kiosks when: I made changes to my ticket (like flt.s), I upgraded to FC with upgrade cert, computer problems. Last year, they gave you bonus miles for using the kiosk. This year, you get 1000 miles the first time you use it.
You get 500 miles everytime you check in on the web though. I usually check in on the web and then check in on at the kiosk or MVP line if I have bags depending on which line is shorter. I like the web checkin because I can leave later (too many early flts in AK!) and get 1000 bonus miles each trip!