I don't know if this is useful to anyone or not (or if it has been posted elsewhere), but I came across this website (http://www.bigorrin.org/wiz7.htm) that apparently has "a good game editor" that you can "use ... to alter your Wizardry 8 codes, inventory, and stats, so if you lost an important item somehow, this is an easy way to give it back to yourself. This program also lets you set all monsters in the game to 'passive' state, if you're really sick of combat."

Direct Download: http://cyberman.agava.ru/f/cht/tr/cm-wz8tr.zip

Again, don't know how relevant it is or if it even works (don't own the Wizzes), but I figured I'd share.

EDIT: Sorry, is this the same as the Cosmic Forge editor that was mentioned elsewhere? I really have no idea

Nah, the Cosmic Forge isn't a savegame editor, it's a game editor. It's used for building mods or just tinkering around with stuff. You can find it here:
http://mad-god.webs.com/cosmicforge.htm

Personally, I like to use the two savegame editors here, down in the "Wizardry Editors and Data Viewers" section. The nice thing about the item editor is that you can modify the data file to allow you to add custom or mod-created items into the game. The nice thing about the character editor is that you can adjust your skills independent of whether those skills are "open" or "closed," which is quite nice. Note that these are actual save game editors. The link you posted was to a trainer, which runs along with the game.

bump

Just to keep Cosmic Forge Editor (for Wizardry 6-8) in people's sight.