Radiation analysis, Honeybee (Radiance) versus Ladybug

Hello everyone, 

I shall first of all thank you for the Honeybee and Ladybug tools, which are simply splendid.

I am always dealing with radiation analysis  process. I tried to move on to Honeybee in order to benefit from all Radiance pros and advantages. As Honeybee is a wonderful tool, I did not find any obstacles to erect the Radiation analysis program for a simple geometry (mainly surfaces). As expected, the analysis was performed successfully. 

In order to substantiate Honeybee results, I carried out a similar analysis in Ladybug , considering the same geometry and the same period analysis. Moreover, as expected, both analysis lead to the same irradiation (kwh/m²) distribution on the considered geometry. This first conclusion validates the coherence of Ladybug and Honeybee radiation analysis components. I made this verification by subtracting  Ladybug irradiation to Honeybee irradiation on a set of test points.

Since I want to evaluate shading devices efficiency, I rotated the model geometry in order to mimic all facades orientations and configurations (North, South,Est ,West) . Unfortunately, this rotation ( for instance by 10 degrees) induces  differences in terms of  results, so Ladybug irradiation distribution is not matching Honeybee distribution (Radiance) anymore.

Furthermore, I have found out that translating (geometric transformation) the geometry in a horizontal plane does not impact Ladybug irradiation results,which seems correct, but does affect Honeybee outputs.

In other words,I could not figure out how rotation or translation affects Radiation analysis in HoneyBee ?

The enclosed file/image shows the analysis program containing Honeybee and Ladybug radiation components.

Have any of you guys been in such problematic situation before? 

Mostapha, I would be very pleased with your contribution within this issue.

Thank you in advance guys.

PS:I joint a picture of canvas program as well as Grasshopper file.