I tried to import the new mame 0.254 full set with my Launchbox 13.3 today.
The Launchbox got no response and load forever...
Before 13.3 it should be very fast.
My computer is a monster, 13900K, 64GB DDR5. RTX4090. It should be more than enough.
Edited: It finally completed after I tried five more times...