Creality is awesome!

I've seen that Creality is offering Creality printer owners a special offer to those who back the CR-Scan Kickstarter project. I believe this allows one to get the next model up at the same price as the lower model. Can someone provide the details on how to sign up for that? Also, I have an Ender-5 Pro and need to find the serial number for the printer? Is that printed on a label on the bottom of the printer?

I just received my new Ender 5 Pro and I'm trying to connect the Capricorn PTFE Tube to the Extruder. When I push the Tube into the extruder and place the blue locking ring on, the tube just slides right back out. Isn't it supposed to lock in place? Can someone please explain the required steps to get the tube and extruder properly setup. The instructions also didn't provide an exact location where the extruder was supposed to be placed on the rail. Does it matter?
If it does, can anyone provide a recommended location where the motor should be placed?
Obviously, I'm new to 3D printing, so I'm sorry if my questions are a bit stupid. Appreciate any help. Thanks.