ASk, I thought you would have known by now that custom animations are possible
we just don't have a clean, easy, and fun way to do them at this moment.
I'm writing an animation program, but it's not nearly done, it's had a lot of progress, but I'm still a long ways off from finishing.
I looked up your website and I think it's a great mod idea, I'm glad Gabe is behind it, but I do worry about fitting your models around the humanoid skeleton, or making your own models' animations.
I wouldn't shy away from making your own animations, it adds to the slickness of the effect, but you might also want to target JA as your mods platform, or perhaps you should make an ernest attempt at fitting a PA model to the existing skeleton, it should 'kind of' fit.
Worst case, recreate the _humanoid skeleton in your PA models proportions, I have been working on ripping animations from the JK2 _humanoid.gla to a format I can work with, soon enough I'll be able to rip them to the correct position finding format, and rebase them (apply them to a similar skeleton, such as your new _humanoid)
However, documentation on my tools is very ... non-existant. Why? Because I'm the only one who uses them (they are not very user-friendly atm) and my reasons for making this tool are my own, but I have a lotta help from peeps at #jk2coding on quakenet.