Hi Edward,
i am not really sure what you are trying to achieve in RTL. But here are some guidelines :
As long as your signal or custom indicator formula is associated to a single instrument, then there is no issue.
If you want to mix information in the same formula, aka create a combined signal that would pick up information from 2 separate signals, each associated to a different instrument , then you will most probably need to use MPD tokens
Lets say on a chart, you have ES but also ES buy volume and ES sell volume instrument, possibly with some size filter
In the setup of the MPD token, you have
1) the possibility to select a size filter
2) the possibility to refer directly to the "buy volume" information by selecting it as "instrument data"
Alternatively, you could refer (in the MPD setup) to a signal or CI that would use as instrument data the "BUY volume" in its own information
This means that if you don t use any price filter, you may not need to use a MPD token IF all the RTL formula are associated to the main ES instrument..
Might sound a bit confusing, but there are several ways to mix information coming out the same but filtered instrument (filter being bid only / ask only and / or a size filter on top of that...)
If you would provide a bit more infoirmation about what you want to achieve, I am pretty sure there are straight forward RTL solutions, using either MPD or RTL access to "fundamental" instrument data information that i could share
Cheers
Eddy
PS : in the screenshot hereblow, a bit more information about these special "price sources" (whenever it was first introduced in IRT 10 years ago in version 11.2..)