I studied abroad in England my junior year. I was lucky because I didn't have a language barrier, which definitely helped when I caught my compressor on fire the first time I used it (on a sidenote, I apparently never learn, since I also ruined yet another compressor during a recent trip to Turkey). My advice is to buy a compressor (they aren't actually that expensive in Europe) for the country you'll be living in, rather than trying to take an adapter. At least my experience with the Pari Proneb is that if you try and use it in Europe, converter or no, you'll ruin it. At the time I was using IPV, which was a pain in the ass, but it worked. If you have a 104 or 105 model Vest you should have no trouble with using an adapter -- they have a built in frequency converter.
I brought meds with me, then restocked when I was home for break (also did IVs). I had been given contacts with CF centers in England and Ireland (I have family in the latter) before I left, so that if there was an emergency or I needed a hospitalization or a local prescription I could get it. My travel insurance worked internationally but luckily I didn't have much cause to use it. I learned very quickly on that trip that I had two choices: 1) be uber on top of meds and maybe stay healthy enough to enjoy my time there and make it worth it (I realize there is always luck involved here too), or 2) slack off and get sick really far away from home and be very sad. Needless to say after week one, which involved a few too many very late nights and extra beers that led to that "oh, I can skip TONIGHT" attitude, I chose the smarter route.