I've done a bit of hex editing and config editing. I still know some old dos commands and I am learning Doom code and syntax by editing DEF and DDF files in Doomsday Engine and the EDGE source ports, respectively. I plan on learning DoomBuilder and SLADE in the future as well as C++, so I can make mods for Quake1 and Quake2 some day. I would like to create my own games in the future and work with an indie dev team at some point.
This video shows you my latest work on Doom 64 Absolute Perdition(BETAv1.0) Here can be seen my vaDoom2 monster riants and the weapon changes I made. As well as some of the other features I have implemented, like the exploding barrels that you can launch at an enemy and the shootable rocket pick up items. If you like what you see, then please try it!