Hi, shirish, thank you for your interest in my project! I presume you're on GNU/Linux, there are instructions on compiling the game engine, called ZDoom here: http://zdoom.org/wiki/Linux

Zauberer is to be used as a so called IWAD, and should be placed in the same directory as ZDoom, or any other place mentioned in the article I linked under the chapter "Start playing ZDoom".

If all goes well, you should have a titlescreen which says Blasphemer which is just temporary and you will have a working menu system, but trying to start a new game will just give an error message in the console. That's because there is no map in Zauberer yet. That's where the addon .wad files come in. Addons for this game can be downloaded here: http://www.doomworld.com/idgames/index.php?dir=levels/hexen/

Then just use the command zdoom -file yourwadfilename and it should hopefully work.

If you run into any problem, don't hesitate to ask and I will do my best to help you. :)