"BTW , the script uses XML::Simple which i guess needs the XML::LibXML package since i don't include anywhere XML::LibXML."

There's no need to guess, check the dependencies.

"But when i run the executable it says "Program too big to fit in memory" which can't be a real issue since the exe has 3 MB and i have a bazillion RAM."

Perhaps there's something fundamentally wrong with your code. Post a small example of your code which reproduces the problem, any test data (some XML? Give details on the file size you're dealing with etc) and your pp command which you use to generate the exe.