Anyway, just right click a compressed overlay in CrystalTile's NDS filesystem explorer and you'll have the option of decompressing and saving it or opening a decompressed file and compressing it to that location. The process once you've got the decompressed overlay (#74) is easy enough; do a text search in a hex editor for AXVJ. It'll find a small list of game IDs for the 3rd gen pokemon games in which you can replace all J's with the letter corresponding to your language and vice versa. Save and compress/insert the edited overlay and you're good to go. Any 4th gen game can be hacked to accept any third gen game in a similar manner.