Download the latest build of EDuke32 and my drop-in stopgap, and extract everything to your World Tour folder, usually "C:\Program Files (x86)\Steam\SteamApps\common\Duke Nukem 3D Twentieth Anniversary World Tour", or wherever you have installed the game.
Then you can run eduke32.exe!
What is supported:
All of the World Tour CONs, including the new enemy, boss, and minibosses.
8-bit parallax skies.
Original VOC files.
Lee's new renders of the original music.
Polymer lighting added by the original mappers.
Normal maps for the original art. (For the time being, normal maps only work with r_pr_artmapping 0, for the same reason texture filtering is incompatible with the artmapping feature.)
Widescreen weapons and status bar.
New Duke voice acting. Use "setvar voice <value>" in the console to configure. 0 - 2016 voice, 1 - 1996 voice except during Episode 5, 2 - 1996 voice except new lines only
Developer commentary. Use "setvar commentary <value>" in the console to configure. 0 - off, 1 - on, 2 - show but don't allow playback
New touchplate settings: pal 2 is co-op only, and pal 3 is Dukematch-only. This is in addition to pal 1 being single-player only. Some Alien World Order maps cannot be completed in EDuke32 without my code to take care of this.
The new cstat bits used by World Tour to "ignore lighting and SSAO effects" are scrubbed so our engine doesn't interpret them using our meanings.
The Incinerator is unimplemented.
Multiplayer (blue (and red?) palswapped) Incinerator pickups are not deleted in single player.
The Firefly and BOSS5 don't have any of the new projectiles.
Some breakable objects remain unimplemented.
I haven't added the Armor box to the classic mini-hud, or the slight adjustments to the full statusbar.
The episode 5 ending.
Need a def token to invert the green channel of normal maps.
I've spent the better part of the past three days working on this, and I need to get back to my regularly scheduled programming. The original game is completely playable with the new additions. The new episode is mostly playable.
I am not interested in spending the time implementing the Incinerator or the new projectile(s). I welcome contributions if they meet my standards. I also welcome any and all feedback. I have not actually played the new episode beyond part of the first level, and the final boss level.
By all means, spread the word.
Always bet on EDuke32.