animation try on

what sort of script is needed so that when someone clicks on a picture of an animation they can try it on for 15 secs or so?

use a standard pose stand script ?

That's the usual approach to such things.

but doesnt a pose stand script just make the person do a 180 turn and then t-pose?

The standard pose stand does exactly that. However if you replace the T-pose animation with the animation you want to demo it will play that instead (as long as you also change the script to reflect the new anim).

With the inclusion of some buttons you can cycle through different animations and have a demo stand for a number of poses in one box (as it were).

I had a look inside a pose stand contents but there was no animation in there. Just a script.

There are many pose-stands available that let you drop animations into them and cycle through the whole set. The reason some stands don't have an animation in their contents is because they reference a "default" pose (usually the T-pose) that is referenced within the script itself.

I've seen several pose-stands for sale (and sell one myself for L$135) and there are others available free. It's just a matter of finding one that suits your needs.