in reply to Losing my memory
Not sure but from your description what's happening is even though you're calling the destroy method on the Tk widgets you're not removing the references to those widgets from your hash %TK so the underlying resources those are using aren't going away. I'd bet if you also did e.g. undef $TK{'pw-'.$NVP{'Id'}} after calling destroy you'd see things clean up much more completely.
The cake is a lie.
The cake is a lie.
The cake is a lie.
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