HiA voltage on the wave over a determined level, noise spikes are fine. That's correct on the fuse.
HiBuild: July 3, 2018 (latest)
It's not randomly freezing, it's going very, very slow!
I've attached the asc file (it's a bit different as I've been playing around to try and make it simulate).
I also wonder why LTSpice copies all the models/symbol files into the users home directory and doesn't sync them.
Try adding a few ohm resistor in place of the fuse in the model because spice models don't like infinite current circuits. The crowbar is supposed to represent throwing a crowbar across the bus bars - infinite current and blown fuse.Thought so, any input to the gate caused LTSpice to die.