Not sure what to say, other than the title. The link to the save game is here: Dropbox - stonehearthsave.rar
I was building a tower and then couldn’t place any blocks anymore. I saved and reloaded. Game was laggy and the UI was even more laggy. After a few seconds, the error popup appeared and made it to around 3300 before I Alt+F4’d it. I had to Ctrl+Alt+Del and force the process to end.
No idea how to classify this. I should also mention I was using version 10.5.3 and one mod (Zulser’s Conveyor Belts).