In @cvstemp and @arraytemp, you append the new lines always with a newline \n at the end. You most likely don't want that newline.

I found this by searching your source code for \n because you mentioned "newlines".

Also, you don't need to split and rejoin your data all the time. You should be looking into perldsc to find out how to store your spreadsheet as array of arrays or array of hashes.