What/where is the "special command"?
Within the macro create function there is a drop-down list on the right side. Select "RF commands". I've downloaded the Marmitek software and verified that this works with both my CM15a and TM751. You hardware is a bit different (frequency) but the function should be the same.
This could be a "minimal" way of getting into X10 without spending too much (yes I tend to be a minimalist - much to my family's chagrin) . As I noted above, if you can't communicate reliably over the powerline, you will be giving up quite a bit using the RF protocol with Marmitek units.
To be honest, I wouldn't go into this type of project without a path to reliable powerline communication. In my opinion, you are paying a lot for Marmitek units with advanced features, and not using them. You may want to investigate a repeater to improve your poweline communication. I know that Jeff Volp has some cutomers In Europe and I have tremendous respect for his XTB-II repeater. This would be an alternative to RF communication that would take advantage of the capabilities of the Marmitek 2-way modules.
Jeff has a web page for his repeaters here:
X10 Transmit BoosterLet us know your thoughts,
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