Sure, so you would likely need an engineer to help out with this. But the code implementation should be trivial. You would add this function to a blueprint library class - they allow you to expose native functionality to blueprint and/or python that isn’t accessible in the vanilla engine. In the example I sent over previously, I used USequencePlayerLibrary which is an engine class, but you should be able to have a new blueprint library class added within your project (or re-use an existing one) into which you can add a function similar to TriggerTransitionOnLooped that I shared. There’s more about bp library classes in this [knowledge base [Content removed]
The way that I set things up in that code - with the struct to hold the data, etc - is just one way to do it, but there are various other ways you could achieve the same thing in code or blueprint. The important thing is that you need to be able to access GetDeltaTimeRecord()->GetPrevious() and GetAccumulatedTime() on the sequence player to know that the animation has looped. Note that you would also probably want to deal with the case where the animation is playing backwards.
In terms of the three questions that you asked, could you give me more information on what the use case is? For instance, are you trying to add variation into the idle by having the number of loops change each time? It’s a somewhat uncommon request, which is why the information you need isn’t exposed by default (but there are many other uncommon use cases that we also don’t cover with the existing API so this isn’t the only one).