tnjk

Thanks, that is clear. I guess the keyfob has a transponder. For my other car, an Audi A2, this works about the same: only new keys can be programmed, not keys from a donor audi. My way around that is to remove the old glass-housed transponder from the key, and put in a brand new ID 48 transponder, that works. The transponder is very cheap on ali, only a few euro's, whereas a new key from the dealer is more than 100 euro.
Looking at the MGTF keyfob inside there is a different kind of transponder, not a glass one, but the coil is soldered, or glued, on the small PCB so it might well not be an ID48, but a different type.
Anyway, having two sets of fobs, beloning to each pektron, is very inconvenient, so therefore the clone idea.
So I will give Paul an email, see what he thinks about it. I am a bit worried about the package getting lost in the postal services, perhaps I can insure it at a value needed for a complete new set: ecu, pektron, 2 fobs.