I read the version on here supports XP and VISTA ( though i guess is emulated through dos ); but what about WIN7 ? Anyone has information?

It works fine for me in Windows 7. There have been some small issues with user permissions with 7 however. You will want to be sure you install it to a directory you have full "read, write, execute" permissions to for Blood to save your game, or to launch Cryptic passage.
Consider installing it to your username directory rather than the default Program Files
ie: C:\Users\your_user_name\programs

permissions shouldn't be a problem , i disabled the UAC because many other games and programs give the same problems with access.

I have UAC off on W7, and didn't have a problem with Blood, or other GOG DOSBox games. It should work fine.

It's up to you if you want to disable UAC, but you don't have to compromise the built-in security measures of Windows 7 in order to run Blood. Just be sure you have the proper permissions to the install directory and it all works fine.

Another question about the game ; the version downloaded here has any of the expansion packs included?
edit : ow i just saw it in the vg page ><

working fine for me also win7, only problem i had was with multiplay, had to give system full control of commit dat file, all is fine now !