When I hide and show labels using shortcut I get this:

The mod Utilization Monitor (Blargh) (0.8.0) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event UtilizationMonitorBlargh::on_tick (ID 0)
UtilizationMonitorBlargh/control.lua:137: attempt to index field 'label' (a nil value)
stack traceback:
UtilizationMonitorBlargh/control.lua:137: in function 'update_label'
UtilizationMonitorBlargh/control.lua:488: in function <UtilizationMonitorBlargh/control.lua:438>

Now fixed in 0.8.1 - thanks.

Victim of "oh one last quick fix for 0.8.0 release" and while I rechecked all the units and the settings, forgot to check the keyboard bindings and it bit me.

Will post 0.8.1 here in a few after finishing checks.

0.8.1 posted now.

Fix confirmed. Thanks!