use lib "C:\path\to\my\script";
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likely won't do what you think it does. \t expands to a tab in double quotes.

I prefer to use forward slashes in path specifications:

use lib "C:/path/to/my/script";
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Also, I like to launch my Perl programs through a .cmd script on Windows:

@rem Change the directory to where this .cmd lives:
cd /d %~dp0

@rem Launch the script
perl -w myscript.pl %*
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That way, I have a defined working directory, which also makes relative paths work again.