The problem with it (if you can call it like that) is that the utility that converts Doom maps into UDMF didn't work as I would expect. What it did was to transform all the data of a Doom map to a text file, which is okay, but it did convert the map into the Doom namespace (and not ZDoom), meaning that LINEDEF and SECTOR specials were just passed and not converted. Although the map converted this way is perfectly playable, loading it into Doom Builder 2 (the only map editor with UDMF support) would cause headaches.
Since it was easier to copy a map manually and then change Line and Sector specials by hand, there wasn't much use to this program. So, I took some liberties and added the ability to transform every Line and Sector special from Doom to UDMF, so you don't have to do it manually anymore. Note that it doesn't convert BOOM specials
Here is the Win32 binary
To convert a map from Doom format to UDMF, the usage is as follows:
For example, to convert E2M4 from Doom, you should do this:
Then, open your generated text file and in the first line, change 'namespace = "Doom";' to 'namespace = "ZDoom";'. After that, open a resource editor (preferrably Slade3) and create a new WAD document. Inside it, create three lumps in this order:
-Your map name (example: E2M4)
-a TEXTMAP lump (and inside of it, paste everything from the generated text file)
-and finally an ENDMAP marker.
Save it and the map is now loadable in Doom Builder 2, with every Line and Sector special already converted to their UDMF equivalent.
BTW, I'm a n00b into C++, that's why the source is a mess now.