Teleport - llSitTarget, Changed Event and Linked Prims

I am developing a teleporter script. I'm using the llSitTarget and Changed Event with llSetLinkPrimitiveParameters to change the avatar's prim position. In testing I've noticed that the prim with my script in it has to be unlinked or the teleport will fail (dropping at the teleporter prim's position). Is there a way to have a linked set of prims (with the script in the root) and get it to teleport? I tried it with newly created prims, linked them together and still can't teleport unless the root prim is unlinked. Ideas? What am I missing here?

You aren't missing anything, the function is in a somewhat buggy condition at the moment. some restrictions were placed on distances to avoid griefing, but they kick in too early.

The problem with link sets was actually there before the 1.23 server, but the latest changes make it even worse.

For now, you'll get a reasonably reliable teleporter with one prim, at zero rotation when the child avatar is moved, Anything else, you are dependent on sheer luck.