I have never used automation a lot so I am total rookie on that. However, I need to use it now as I can't test a specific strategy without it. I have tried to create my own automation rule but unfortunately I failed miserably at it, losing a fair amount of money in the process.

So, I turn to this forum now in seach of help, as I am pretty sure that what I want to create is actually quite simple for any seasoned automation rule creator.... I just can't get it to work properly.
Anyway, what I want to do is to have an in-play rule set up which will automatically back a runner if it's in-play odds drop to a specific level, say 2.5. This rule may only trigger once per horse, but any horse that drop to the odds required should be backed. I have tried to create this rule but either it only backs the first horse to reach the odds level, disregarding any later horses to drop to the required odds, or it backs all horses in the race at the odds they're on at the time, once one of the horses reach the odds set (2.5 in this example).
So, how do I do that? Any advice much appreciated.