The control system allows you to set values of variables from different projects of one workspace in one recipe.
Now the variable selection dialog opens.
Here you not only can select variables from the I-PRO, but in the left area you also can select other projects. You will then get the variable list of the according project and can select variables from it.
As the I-PRO is a client to the servers PRO1 and PRO2, this will work without any problems in the Runtime.
The control system does not care, whether the network structure in the Runtime really allows access to the selected project and its variables!
In the Editor you can e.g. select variables from the I-PRO and the project PRO2 for a recipe of the project PRO1. But this will not work in the Runtime!
In the variable list of the recipe the project name is written in front of the variable name.