Ok, that should absolutely be doable. If you intend to use my newest update, however, I am tempted to wait until Epic upload it. I’ve changed AI a lot, so telling you how to do this in the old system will not be as helpful. The marketplace guys told me they would have it up very soon more than a week ago, and I sent them the update before Christmas so they are quite a bit overdue. I’ll pester them some more and then I will try to help you implement the guarding functionality after it is uploaded. In short though, what you want to do is to check all tiles in move range for defendable tiles (possibly using an array to designate which tiles should be defended). If one is within range, make the unit move to this tile; then check tiles in sight range for targets to attack from its new position.
Ok, not too surprising I forgot about that 
Synchronous resolution is pretty tricky and not something I have thought of very good ways to solve. I might put my mind to the task at a later point, but it is too big of an undertaking to solve with a quick brainstorm. I have solved your other question, though. I thought making it possible to cycle between your units would be very easy, but it turned out to be a much bigger challenge than I anticipated. Here is my solution which uses both ATBTT_GameMode and ATBTT_PlayerController:
In ATBTT_GameMode (a new function):
In ATBTT_PlayerController (in the event graph):
So what I am essentially doing is moving every player unit in the Initiative Order array one step to the right or left, moving the one that either gets to index -1 or to the index of the firs AI unit to the other side of the player’s “half” of the array, then activating the unit on index 0. Hmm, not the best explanation, but you can hopefully figure it out from the graphs. Seems to work really well, though!