ExcalibursZone - just seen your rant in Chit Chat so thought I'd give this a go. If it doesn't work there are other things that may be causing your problem -

Tactic Number One :

Make sure you haven't got a public reference in the dll to something that's been passed byRef to it. For example, if you pass the players byRef then store them in a dictionary, which is used throughout the dll, you are effectively creating a link from the dll into the caller. So, when you set the object to Nothing in the caller it can't destory it because there's still a reference in existance coming from the other direction. Before setting the object to nothing in the caller try running a tidy up routine which destorys the items in the dictionary and anything else that is using byRef so there's no links from dll to caller.

Basically this is called a circular reference and it's the biggest reason for objects being left in memory when they should have been destroyed. ( .Net cures this by the way ).

A -> B -> A : Destory the link from B to A before A to B

Hope that isn't as confusing as I think it is but I'm a bit busy at the mo.