Yes, there is a halo custom edition.
Well, Halo Custom Edition is the multiplayer version of Halo Combat Evolved PC. It doesn't have a Campaign, by the way. If you want to get Halo Custom Edition, install the installer and use your Halo Combat Evolved PC Key. The main advantage of Halo Custom Edition is custom maps. Halo Custom Edition is currently in Version 1.0.9.620
in halo combat evolved u cant create ur own stuff in halo custom edition u can
Halo Custom Edition is FREE.You can download Halo CE from http://hce.halomaps.orgTo install Halo CE you need the original Halo Combat Evolved game.
You install it then play it from the shortcut.
From what I heard, yes.
MAPS
You can download a demo version of Halo: Combat Evolved for free on the internet. There is also the Halo: Custom Edition, but this requires the CD Key of the full version of Halo: Combat Evolved installed on the computer you install Custom Edition on. Custom Edition is free, and allows for the use of user-created maps. It does not include the campaign though.
You can't cheat unless you have the Trial version of Halo Combat Evolved or you have the Halo Dev Trainer. You can also cheat on the edition to Halo Combat Evolved which is just a standalone version called Halo Custom Edition.*Please note that the cheats found online can only be used on the Halo Custom Edition and the Halo Combat Evolved Trial version. The retail version CAN NOT BE CHEATED on unless you have and are a modder.
The same as the one for your Halo Combat Evolved Disc
Ignore the links below if you don't have the custom edition.
It should say on the cover of the game box/case.
Halo Custom Edition.