Hi! I cannot use the function "edit relations" well. I want to set many relations between two layers but only one relation can be set. Moreover, when I set one relation between two flows in energy layer, it said that the key flow does not exist in the variable vector!
Please download the latest version of STAN. There, a few issues with additional relations have been corrected (unfortunately not yours): It seems that if there is no data given on a layer/period, the respective variables will not be set up, even though they are included in additional relations. This is definitely a bug, that we will correct in the next version. Thanks, for pointing it up. Here, a temporal workaround: state at least one value on a layer/period where no data is given.
To add a new additional relation, click in the empty field below "expression" and then the appearing button with the three dots.