My crossfire garage door opener (CGDO) had the buttons missing when I bought the car. Who knows why. Today I was able to buy a used one I removed from a wreck and decided to program it. First off, getting the thing out of there was a pain. The catches on the top are a bear to release, and they stick on the cloth of the headliner. I KNOW THIS HAS BEEN RE-HASHED MANY TIMES, but this might enlighten some others. The confusion is from the Xfire instructions. They don't explicitly explain that you have to use an existing functioning remote for your garage door in the procedure. Your original remote is used to "train" the CGDO as the CGDO is able to adapt to different frequencies and code styles. That is why they want you to hold them together for a bit (pressing a button on both). At this point the CGDO can mimic your original remote. During this step I unplug the actual garage door unit just to prevent the door from going up and down. After that you power up the actual garage door opener, press the learn button, and press the CGDO button you programmed. I followed this and it worked first time. The reason some have success with just the learn buttonprocedure is that the CGDO is already in the correct frequency and code mode. If someone needs a CGDO and yours has buttons, it is available, pm me.
Apologies for redundancy