Thank you very much for bringing this to our attention, @AntonH . This was a pretty major bug that was causing us to count the direct contribution of sun twice. I just pushed a fix to the development version of the plugins for this:
You should be able to get it on your end with the LB Versioner within the hour.
This is a large enough bug that I think we may move up the release of LBT Grasshopper 1.4 so that more people can access it sooner. Thank you, again, for bringing it to our attention.