I am using an APC Back-UPS ES 350 (Model BE350U) connected via a simple signalling USB cable.  And although it is a simple signalling cable, on one test machine which has apcupsd installed, it reports smart-like information, much more than one would get with dumb voltage signalling.

But XPM reports under Power Information: UPS:

Attribute - Value
--------    -----
Device - ups_hiddev0
Type - UPS
Power Supply - True
Energy full design - 0.0 Wh
Energy full - 0.0 Wh
Energy empty - 0.0 Wh
Voltage - 0.0 V

So it seems that XPM is not communicating with whatever backend it uses for the UPS, or the backend is not monitoring effectively.

Needless to say, I have no confidence that XPM will actually execute a graceful shutdown of the system in the event of a power outage.

Is this a known issue?  If it is, has it been fixed in the current release?  I don't know a thing about how XPM works with its backend(s), but I know that apcupsd will accurately monitor this UPS.  Can XPM be configured to use that as the backend?