I discovered the new RockBox Utility
and, as a result, installed the new bootloader (v4) and the latest RB build (I had been using a MaxWen build that was older.)
When my X5 is off, why does a 'short' push on the sideswitch make the screen come on and display "shutting down"?
(And it took me awhile to figure out that the new bootloader is not the same as the (old) DUAL-bootloader!)