Recall value of a variable whose name contains another variable

[tiffle]

You need to use the Filter action as described here:

What does "Filter Variable ‘Variable’ with Value of Named Variable" do?

If replaces the variable’s value with the value of the variable named by the value of the variable in question. Basically, it is an indirection, allowing you to read the value of a variable whose name is in a variable. It is the equivalent of Set variable Name to %Variable%(%Variable%Name%)% which does not work and which you can’t do easily. It is equivalent to Set variable Name to %%Variable%%%Variable%Name%%% Filter Variable "Name" Process Tokens