Hey guys, I tried loads of these solutions. Replacing meshes and materials that had duplicate names. Checking hard drive space. Disabling firewall and anti virus software…
In the end I was trying deleting assets one by one and while checking to see if I could do a light build. I eventually found one that SEEMED to be causing the error. But once I reloaded the original level (without making ANY changes or deleting anything)… it worked fine. I’m no closer to understanding why the swarm was failing to kick off, but it seems like if you screw around with your level enough it just decides to work :-/