I believe the problem with your code lies in the quotes around the numeric values.
Try: 
my $MW = MainWindows->new(-width=>600, -height=>600);

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Cheers, Akoya

In reply to Re: Perl/TK: How to set the width and height of the main window? by Akoya
in thread Perl/TK: How to set the width and height of the main window? by MyFSL

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