I don't really have a negative impression (other than the cost ). I'll need to study the documentation a little more closely. (Is this the best source?) For example, looking at the documentation and the (repeating your) answer to my first question is 'yes' by creating an observing plan with dark frames as the only "targets" e.g. if it's a dark and stormy night and all I want to do is take calibration...

; take duskflats (configured for a flatscreen) then 15 each of 1s and 30s darks
# DUSKFLATS
# Repeat 15
# Interval 1
# Dark
# Interval 30
# Dark
# SHUTDOWN

And the plan will run without rolling the roof off?