Use the example code with the model 'potion bottle' as its reference but make it (the model) invisible.
I remeber Geoge wote a script in Q&A but cant remeber which one, am currently researching...

It concerned clicking a model path system and the player or NPC moving to each created model node then on to the next after some time there.

Might help

**...and try swapping ignore passable with glide