This game requires the "Indeo Codec" (Wikipedia article[en.wikipedia.org]) to play cutscenes, but it has two problems.

• This is a really old codec, and no reliable sites distribute it any more. If you have winetricks/protontricks, the installation command is "icodec", and it tries to download from http://www.cucusoft.com/codecdownload/codinstl.exe, but it's dead since 2025. To overcome it, you can download the old snapshot from the Wayback Machine, for example from https://web.archive.org/web/20241217170639/http://www.cucusoft.com/codecdownload/codinstl.exe
  
• The other problem is that this codec has vulnerability. (See the above Wikipedia page.) So do not install it systemwide. Instead put it in the same folder as the game's .exe file.

The first savepoint is the home of the protagonists. There you can save by speaking to your partner. Same for other savepoints.

The original game (2001) was for mouse&keyboard, and this port also has some inconvenience for the gamepad. Remember you can use Steam Input to improve the situation. (I used D-pad for quick equipment change, but you probably want to change it after actually playing for some time.)

During the gameplay you see insturction screens a few times like this:

You can see them in the Option menu, therein choosing "foods" 1 2, pet, etc.

There are Lv20 dungeons that are not related to the story. They are really difficult; I suspect they really meant Lv30. So never get serious about them at Lv20.

* I recommend to read also Beginner's Guide to Zwei by RPG Gamer Man, a short but really helpful guide.
* There's a walkthrough at gamefaqs: https://gamefaqs.gamespot.com/pc/567436-zwei/faqs/15519 . It was for the original version in y2001, which was only released in Japan, and in the walkthrough terminology differs from the Steam version, but it helps.

That's all. I hope it helps and you enjoy Zwei!! Thanks for reading.