Re-naming APK's

[Guest wbexpress]

Hi Paul, this is Paul from Philadelphia, PA. Great app, obviously the only one that can back up paid apps, you're the man! Question: (I checked the forum, could not see anything on point). I believe due to a new ROM or Google issues, a few of my paid apps will not show up in the Market. I did back them up with TB, and I am trying to transfer them from the one phone (MT3G) that shows them to the other (G1). So, I go into the TB folder on the computer (actually, the SD card that is open), open it, copy the APK to the computer and rename it. {They are called "gz" files(?)}. Anyway, I rename it to an "apk" file, and when I do it shows on the desktop just like a regular APK file (with the little icon that looks like a Windows media icon), then transfer it to the G1's SD card. When I use Apps Installer to try to install it, I get an error message that says "trouble parsing the package. Obviously I'm doing something wrong. Can you tell me what it is and what the correct way to do it is? Thanks...