It didn't work. I'm using Windows XP service pack 3.
I don't know if this makes any difference but I don't have an internet connection.
Whenever I need to download something it's either net cafes, friends' houses or the university lab.
Anyway, I used that link you provided to get .NET Framework 3.5. There seem to be two different installers for it.
The dotnetfx35setup version (2.7Mb, I think it's refered to as bootstrapper or something) would get endlessly stuck while trying to download another 70Mb and then I'd have to terminate it with the task manager.
The dotnetfx35 version (197Mb, the full redistributable) again tried to download an extra 70Mb. It somehow got up to 60 (that's what it showed on-screen anyway, 60/70Mb downloaded), then decided to finally install itself and flashed me a 'Setup is complete' AND a 'Setup has encountered a problem and needs to close. We are sorry for the inconvenience. Please tell Microsoft about this problem.' message at the same time. I exited both messages and the computer asked if I wanted to restart it in order for the installation to be completed. I picked restart and after windows had loaded, I run the game.
Like before it crashed back to the desktop on the way to school the first day, right after Sakaki woke me up.
I tried both easy and normal mode, running the game in a window, running it full-screen, again it crashes. I even tried repairing, uninstalling and reinstalling .NET Framework various times but the game still crashes the exact same way. I also keep getting the 'Setup has encountered a problem and needs to close. We are sorry for the inconvenience. Please tell Microsoft about this problem.' message every time I reinstall .NET Framework. (And don't let me get started on the whole 'Yay, lets download another 70Mb of crap even though there's no internet here and I'm supposed to be a full redistributable'.)
By the way, the net cafe I tried the game at before had .NET Framework 3.5 installed already so I didn't need to bother with it and Zwei would still crash.
The good news so to speak is that at home I get an actual error message.
'Sylph has encountered a problem and needs to close. We are sorry for the inconvenience. If you were in the middle of something, the information you were working on might be lost. Please tell Microsoft about this problem.'
Error signature
EventType : clr20r3 P1 : morningstarzwei.exe P2 : 1.0.0.0
P3 : 49ecccf1 P4 : interpreter P5 : 1.0.0.0 P6 : 49ec7e2b
P7 : 214 P8 : 5f3 P9 : acumen.sylph.interpreter.script
There doesn't seem to be any way for me to copy the actual contents of the error report but here's the dump file from the game.