MRT PTX advice needed

[Lowie]

It's rather simple ...
I have two MRT PTX'es and I would want to use for my son .. so one has to be switched to another PT-number as they are both cloned on my original AMB-pt (which was stolen)

I 've read the manual several times ... maybe it is because I'm not english-speaking but this manual is very confusing.
It's about pushing the button and the led flashing, .. but also about a setup-mode : pushing the button and led flashing, and then there are flashing leds and flicker-flashing...
and pushing the button to change from serie 1 to serie 2 ...
so all about pushing the button and observing the led flashing for different functions...but I can't see any difference

Now I could go berserk on the button and hoping it has switched to another number somehwo after pushing it 18 times or so ... but I can only check tomorrow at the track . and I would like it to be ok before I hit the track.
Plus I really like understanding what I do or changing.

You can find a copy of my manual here: http://www.ludodg.com/RC/images/MRT/PTX_01.jpg

anyone who can help me out here, clear this out for me with understandable and simple instructons.