I've updated the above link with a version of the megaWAD that's had many fixes and tweaks, and a groovy new status bar by P4IR47 on the Doomworld Forums! (screenshot below):

This will be being archived shortly, so if you've not played it and want some old-school action, now is the time!
Here's the highlights for you:
> 32 single-player-only maps, built for limit-removing ports (tested with prboom+ 2.5.1.3 in complevel 2 and GZDoom 4.2.3
> All maps have difficulty settings implemented
> Continuous play is encouraged, but pistol-starting is certainly doable (and more challenging)
> Three cl2 demos are included in the WAD file that should play back in demo-compatible ports
> Every Doom II line action and sector special is used at least once
> Maps start very easy and there's a bit of a lumpy difficulty curve from there, with a couple of properly difficult maps, but generally a pretty reasonable, old-school experience
> No jumping or crouching (ZMAPINFO included for this)
> You can mouselook if you like, but you should be alright with autoaim as well
> Game play mod compatible (but not mandatory)
> > DeHackEd is just for level names and intermission text strings
> > DECORATE just changes the extra gibbed corpses to be green to make my nukage areas look a little nicer - this is totally optional and can comfortably be overridden if your mod requires it

In 1994, the world was changed for the better, when, on September 30th, id software released Doom II: Hell on Earth. Super Shotgun in hand, we took on more interesting, tougher foes over thirty(-two) levels in a continuous campaign, unlike any Doom experience we'd had before. 25 years later, we're still playing, in some way, shape or form.
I'm here to pay tribute to that. Almost exactly one year late, we've got a final edition out and uploaded to /idgames! 32 old-school levels and some other goodies all bundled up for your playing pleasure.
They have all difficulties implemented and should run on basically any limit removing port. Jumping and crouching are disabled by default and would allow you to break progression, so please avoid that! Mouselook is fine with me, though, and as it's all stock, you can use game play mods and the like too! Multiplayer isn't implemented, however. I've tested with GZDoom and prboom+ (default complevel)
Skies are by Mechadon, from his "Mek's Box o' Skies", which is an awesome resource that I highly recommend. I've plucked a silver set of 64x64 computer panels from ZDCMP2 that I think was made by Adelusion, but do correct me if I'm wrong there. MIDIs are variable quality covers of songs I like that have influenced the design of some of the maps, or were picked due to go with the name or theme of the map. Can't say who they're by, as the various MIDI websites online and the file metadata never revealed this information.
Here's some screenshots:



