maybe apache redefines PATH variable before executing the cgi, you should use

use lib 'c:\Perl\lib';
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before any other 'use' statement.

ps:
I don't know if this is useful in this case but i remember apache on win32 interprets the bang path on top of cgi script so you shoud also add

#!c:\perl\bin\perl.exe
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as the very first line of your script.