Yea, I have read many people use the "Brazil" CDA, apparently all people say it's a generic, so definitely worth a try. If that turned out to be not what you want, you can always restore with SEUS or a2uploader.
"Avoid customized CDAs" because you get more than you want! For example, with the customized HK CDA, I got great language support, BUT it also loaded a ton of APN settings for just about every provider in HK(doesn't hurt besides taking up a little space), it also locked down a couple of shortcut keys(> and ^) though this is easy to fix, PlayNow doesn't work(will look into it later, not that important), more junk games and apps you can delete (some in foreign language). So "customized" is not original Sony. "Generic" seems to mean original Sony. It's just never perfect, isn't it!
On the GPS thing, sounds like Rogers didn't get it right with Navigator, AT&T's versoin is quite solid, used it for a month and it was great, very few screw ups. (For people still on AT&T Navigator, please check and download the latest version from TeleNav website, not MediaMall). I've bugged TeleNav to support W760i, other people reading this, please also call/email TeleNav to support generic W760i ASAP! Hate to say it, but TeleNav is just a lot better than Wayfinder IMOH. :) BTW, they are very listening! TeleNav - Contact Us