As a workaround in the absence of any suggestions, I have implemented the following tactics:

The dummy hardware item, event script and user variable can be replicated by adding for example hardware LightwaveRF-2, adding user variable LW-Setting-2, creating event script LightwaveRF-2, and changing ...

I am using the excellent script created by lonebaggie to control my LightwaveRF dimmers via a LightwaveRF Link box.
I have hit a string length issue with the variable LW-Setting used to feed command parameters into the script.
I have 40 LightwaveRF dimmers but I am allowed only about 195 characters ...