OK, a bit of a mouthful - I'll try and explain...
I'm setting a device variable in an expression, to either this bulb, or that bulb, depending on switch position. But the subsequent action using that variable only offers up emulated commands.
An initially defined variable with the same devices does offer the expected commands (eg set level)
I don't think it used to be this way. Am I missing something obvious?
Have you tried staging.webcore.co?
@ipaterson - thoughts?
It's not possible to trace through expression logic to determine what various types of devices the variable might be. This scenario requires the workaround of selecting a different variable that does work, choosing the command, then changing back to the desired dynamic device variable.
If you are setting the variable as shown in the example on every piston run and you don't need to carry over the value from the previous run, just assign a few devices to the ctLights variable in the define section so that the editor works.
Glad I wasn't missing something obvious. I've been using the workaround - but often forget when reviewing old pistons that they still work even though the action editor shows 'nothing selected'!
Yep, this was on staging, as Ian confirmed, it's an undocumented feature 
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