I think what you are referring to is something that for
RoboHelp was only introduced properly with RH6. With that you can
activate on two PCs but any futher attempts will be rejected until
you deactivate (not uninstall) one of the existing installations.
X5 required activation but it didn't check the number of
activations so you should also be OK on X4, or at least that is my
experience.
I can't speak for RoboDemo. My guess would be that if it
isn't on the help menu, then you will be OK. Can you not try
installing a copy on another PC to see if it whinges?
Recently I spoke at the activation people about another
application with proper activation (as in RH6) and found they were
very helpful. I think the link you would require is
http://www.adobe.com/activation.
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