I cracked open the code just to check for myself what exactly is going on. If you're not using RWC, X-Plane sends in a coverage value for the cloud layer that ranges from 1-6. We convert that to a percentage and honor it as best we can.
But sometimes, X-Plane doesn't send a coverage value, and in that case we default to 40% for "scattered" cloud layers, which I think is presented as "few" in the X-Plane UI.
I don't know what drives that coverage value through the API in X-Plane, but the unknown details of that is probably what explains the difference in what you're both seeing. My guess is that FlyAgi's setup is sending in a specific coverage value for the layer to us for some reason, while Prosco's is not.
So... I'm going to lower our internal fallback value of 40% to 30%, as I do think that's more appropriate for "few". I don't think this warrants a new release of SMP in itself, but it will go out with our next update.