Tearing down circular references

It's been a while since I actually made anything nifty in VBA and a recent poster was (for homework I think) trying to make a blackout/lights out game on an Excel Userform here http://www.excelforum.com/excel-gene...ual-basic.html

So I decided to have a crack at it, I haven't posted it in that thread since 1, think it was homework and 2, It raised an issue I haven't had to deal with in a while - circular references. So my question is; in the attached workbook, have I torn down the relationships between the classes sufficiently enough for the memory to be released? Or should I be using pointers to create weak references?

Here's the code if anyone doesn't want to download:

UserForm (with a button on called btnReset)

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Class CLightButton:

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Class ILightsOut

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I've posted a simplified version of this here: http://stackoverflow.com/questions/1...lar-references

Now CrossPosted here: http://www.mrexcel.com/forum/excel-q...eferences.html

and http://www.eileenslounge.com/viewtopic.php?f=27&t=11577