Adding pin constraint to particle in runtime.

[niZmo]

RemoveConstaint(0) line is commented out. I just experimented with it.
And I'm using particleHandle to get the actual particle that is used by some handler I'm interested in.
In general case it could be any particle. I'm using handler just for grabbing particle index.

Oh i didn't see the // lol. And now i see the other code that's commented out that you need. Try to remove the particle from the particle handle first with RemoveParticle(index), then pin the particle. Look at the first link snippet i sent you, to see what methods you need to call before and after. You have them in there already, RemoveFromSolver and PushDataToSolver.

More info here.