Hi racepro
Well I tested your trigger on a bunch of tennis markets and all I could ever get was 3 bets in each market. The attached screen shot shows the end of a match where the favourite changed many times during the match. The highlighted bet is a greenup and it did not fire at the same time as any other trigger.
I think you need to define precicely how and when the trigger is to repeat i.e. what are the conditions for closing the block and repeating the sequence of bets. From what I have observed, the block closes after the first two bets are made and before any greenup trigger has fired. Is that how it should be? It could be the close block conditions (or lack of them) may be the cause of a possible firing at the same time.
I also believe there is some confusion relating to rank and index. I understand you bet when the favourite changes, but I think you need another condition to ensure it is not the same index as the last favourite, because the favourite can change very quickly around evens. Additionally, the program defines the favourite (or rank 1) as the selection with the lowest back price. if both selections have a back price below 2.00, the program will call the one with the lowest price rank 1, but the actual fav could be either. I hope that makes sense. There is a condition to do this in the fav change trigger from a while back.
If I may also suggest; because the intention of the trigger is to repeat, it could be better not to utilise all those greenup expressions in the price and conditions, which may error. Just do all the back bets at level stakes and build a position on each selection. Then green up the market with one green up action towards the end of the match.