linked modulator does work in 5.4.2 through 5.4.29 so
i suspect you’ve come across the slightly buggy behaviour
of calling up the property to link to: you can call up
any modulator easily enough, but then you go to linked
property, and it gives you ‘none’/no list, so you can’t
link to anything.
but this is just because it hasn’t refreshed (or whatever).
try clicking off that modulator, or what you’re doing, click
on another modulator, and then go back to it. try it a couple
of times, and the list does come back. i haven’t quite figured
out/forgot what it is. i think it just needs a chance to update
itself and fetch the list of properties.
you can use a Lua method as alternative – particularly if you
want to link to multiple modulators.
so i reckon it does work. just try again.