Hey, it’s my old thread risen from the dead! This was how my project looked more than half a year ago, and I’ve come pretty far since then. It’s really fun to look at this again, and even more so in that it reappeared on the same day my newest iteration hit the marketplace Trello Boards 
Back then I was happy that I could get the pathfinding to find a path of seven nodes without crashing, while my new system can find every path to every node in a 40*40 grid in less than a millisecond. If you want to follow the progress of the blueprint I’ve since made three threads, in order here (same as Thommie linked to), here and here (from today 
).
Like Thommie said, the first one includes a download link to the old version of the project. I’m not entirely sure I can recommend it anymore, as it is unneccessarily complicated, slow and poorly commented, but by all means take a look! If you’re sufficiently interested in this sort of thing that you would like to buy it, my newest blueprint will be on the marketplace in about a month (provided I get enough votes. Please vote here if you’re interested).
Feel free to ask my anything you want about creating grid based pathfinding in blueprint, as I’ve become pretty proficient at it these last months.
Again, thanks for resurrecting the thread. Perfect timing