Guys, I'm thinking about turning this game into a WWII game, with style oldstyle noTILTangle mechanics, like in wolf3d. What do you think?

Something like this?

Yeah thats pretty cool. I like that it has darker colors than normal wolf. 'thumbs up'

Maybe consider adding something unique in terms of gameplay to do the game though. Like perhaps some special nazi weapons ^^.

No, in fact it's very intuitive and certainly much easier than making maps for modern game engines.

Making Doom maps is pure joy
Back in the Doom days I used Dmapedit. It was very intuitive, stable, and procduced great results. It just didn't have a realtime edit mode like the Build Engine had, but you quickly learned how the numbers you type in all the time will look in 3d

You sir didn't say a thing about the new style

, yes that was probably the editor my brother used too. Maybe that is why it just looked so difficult (and was I young, quess that counts too ).

Now I want to create old school games too

I'm not into WWII stuff at all, so I can't really give you hints there.

The quoted part applies to all editors in use at that time
Actually, a few years ago I had some discussion about editing maps back at that time and the result was A3Tools. For Acknex3 you created maps the same way, just that WED was really minimalistic and that made it a bit frustrating when being used to Dmapedit. If I remember correctly it was a DEU (another Doom editor) spin off, without all the doom specific stuff, so not much of its functionality was left

I take it this one is yours? -> http://www.firoball.de/index.php?id=7
Going to try it out.

, haha that line made me laugh

I also came across this http://www.teaser.fr/~amajorel/yadex/doom2_map04.png , which is based on DEU I think. Looks pretty cool actually.

Yes that's mine. A "write WMP/WMB" feature is missing - since the use of all this is pretty limited I never started fiddling around with that.
I'm not even sure if by now I still understand all the code. I know there was some really tricky and very messy stuff avoiding crashes due to layered walls/vertices.