Looking in the POD for Tk::Image it says:

CAVEATS It's necessary to use the "delete" method to delete an image object and free memory associated with it. Just using a lexical variable for storing the image object and letting the variable to go out of scope or setting to undef is not sufficient.

That said, I tried adding 

    $ZC->centerTags($dwg);
    $img->delete;
    undef $img;

[download]

And it made no difference.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

In reply to Re^3: Hunting for a memory leak by BrowserUk
in thread Hunting for a memory leak by perldough

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