It looks like there is a command line argument for tridef, but can you use the same .exe to represent several different games in launchbox? I suppose you should be able to, since emulators are basically doing that. I'll tinker with it some tonight.
I've done quite a bit of experimenting and also updated Tridef3D to a newer version, however I'm still running into the issue. Supposedly you can right click on a game and create a shortcut, which I've done, an example of the shortcut is: "C:\Program Files (x86)\TriDef 3D\TriDef\TriDefIgnition\TriDefIgnition.exe" -a "Spec Ops: The Line". This will not work at all for some reason. I can launch the game from tridef ignition fine, but from the shortcut the "-a" argument just prevents anything from launching at all. I've tried the command line argument in launchbox, threw an error on me and launchbox wouldn't startup again until I re-made the "C:\Users\username\LaunchBox\Data\Platforms\3D PC.xml". So, I'm a bit stuck at this point. I feel like TridefIgnition has this feature built into it, but it doesn't want to work correctly with it for some reason. Would you have any other suggestions by chance?