On every system I've tried, Recalbox boots up, shows main menu for about 2 seconds, then goes back to black screen with "Booting recalbox" message. Never goes any further. If I try booting again, it never gets to the menu the 2nd time.
I've tested on 3 different USB Flash drives, and 1 250GB USB HDD, and 3 different PCs (Lenova Thinkcenter M91p, AMD Ryzen 5 2500U, and some DELL computer. All 3 PCs are 64bit, however I tried the 32bit as well.
No luck on any.