no experience with that particular plane, but my thoughts are:

1: Probably flies pretty easily. I would guess 2nd plane if you are really confident in your flying, and 3rd if youre a little slower. One guy in our club has a Funtana x100 as his First plane, and seems to do just fine with it. (had some flights on the club trainer first)

2&4: the Nitro Models planes come with manuals that are Terrible in my opinion. At least in my experience) If youve never put together a glow ARF or Kit, and have no one to help you with this, It will likely give you some trouble. (of course, you can probably find plenty of help here) My favorite instruction from the one I got was for the fuel tank... it said only, "Install tank as shown in diagram." That was it, and there was no diagram or picture anywhere in the manual showing a good shot of the tank.

3: that engine would probably pull the plane around, but if you were looking to push it anywhere near its limits, I would reccomend a .72 4 stroke minimum for that type plane. If you just want to cruise around with it, the .52 would probably do you fine.