Windcatcher: 0 values in variable "MacroFlo external ventilation"

[narias]

Hi! I want to know if you can help me with some doubts about a test with IESVE that I am doing

I am evaluating the performance of a windcatcher through a simulation and I had consistent results in Vista Pro in MacroFlo Arrows (l/s). Also I have consistent values of "air temperature" in the rooms selected in the VistaPro variables. However when I want evaluate the variable "MacroFlo external vent", I get a value of 0.(I confirm the variable "MacroFlo external vent" in the Model Browser, in "Windcatcher Duct" and it gives me value 0, unlike the "Windcatcher" where if flow values are obtained).
Something similar happens when I import border conditions to MicroFlo, where the resulting flow rate is minimal and graphically does not seem to cross the damper.

I dont know if this is a limitation of the software regarding these components (windcatcher) or this is an error on my data?

Sorry for my english