If you download the recent version of Garmin's "Base Camp", you can click on "file" then "import", then select the ".GDB" file from the UTBDR zip file you unpacked. It will import into base camp. Then, connect your SD card, or preferrably your 550 to your computer. Then, highlight the "UTBDR All Routes 500" file for example, right click, then select "send to", then select your SD card or 550, and the files will transfer to your device, or SD card which you can plug into your device. I just did it, and didn't need to convert any files to the ".GPX" format, which is another way to do it. If you want to convert to GPX, just highlight the track, and "save as", then select the GPX format with whatever name you want to save it as. Unfortunately, that takes more time, and doesn't seem to be any better. Good Luck!! PM me if you need a little more detail.
Duhfactor screwed with this post 01-27-2013 at 08:09 PM