You can compress all the cheat XMLs with 7zip to a 620kb file only. The normal cheat.zip file is over 30 MB I've tested it with RallyX and the 'Invincibility' cheat and it works.
Parameters for 7zip 9.20 ------------------------ Archiv format: 7z Compression level: Ultra Compression method: LZMA Dictionary size: 32MB (more is not needed) Word size: 192 Solid Block size: 32MB (the size of the extracted directory)