As stated in all devlogs for 1.4a releases, those are alphas and meant for testing before 1.4 stable. Plus 1.4 is now based on Godot 4 / Vulkan which means you may have to stick to 1.3 on this machine.
I cannot repeat this problem, but if you could try to run Material Maker from a shell maybe is shows interesting messages before crashing. Please don't hesitate to contact me (here or on Discord) if you have more information.