This is what I did:
1) I found that MEGAWADS package, posted in one of the threads in this forum. (Heres the link:
http://psp3d.com/showthread.php?t=4549 )
2) Then I went to Fanjita's site, and used that link to Download the DOOM folder/random shiznit. Then I placed the FW1.5 Doom and Doom% folder into my game folder. Note: For me the WADS were missing, so you 'gotta DL them from somewhere else.
3) Then I placed all the WADS from the MEGAWADS package (well, not ALL. Just Quake II and Doom II) into the WADs folder.
4) Optional: I then found the other thread called "I GOT PSIX TO RUN ON MY 2.6" thread, and there is a link there to a site where I downloaded the Half-life WADS. (Link here:
http://psp3d.com/showthread.php?t=4506 )
Those were my steps. It works perfectly for me. XD good luck to you all
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My PsP accessories/games:
1) PsP FW 1.5 (Traded my 2.6 and GTA for it!! OMG YES!)
2) Logitech Case (I'm very paranoid)
3) SOCOM: Fire Team Bravo (Account Name: Terraka)
4) Star Wars: Battlefront II (I'm a big Star Wars fan!)
5) Kingdom of Paradise (It's actually pretty fun. Took me awhile to get into it though...)
6) Grand Theft Auto: Liberty City Stories (Traded... gone... but got a 1.5 instead!)