I founded bug when trying mirroring luminaires. When mirroring at Y-axel there is no effect when trying to change value of "Axis X [m]".
The same problem occurs when creating masts and mirroring them. I can adjust only value of "Axis Y [m]", but adjusting "Axis X [m]" there is no effect. Also when rotating individual luminaire of one mast, there is no effect rotation of luminaire on second mast.
I tried with Siteco Rolf-file and mirroring worked better. But with Rolf file "Mirror at X" caused mirroring at Y and vice versa.
But with LDT file the effect with same parameters is the following:
Dear Tomi Eskelinen
Your first question: The luminaire used was not measured correctly, so you need to correct the lighting details manually.
Open the product selection and pick the Bubo luminaire and select "Beam direction" to change it according to the picture below. It is important that the line points in the same direction as the photometric curve.
Now use the Mirror tool to place the lights and adjust the rotation of the first luminaire in the group so that all others rotate correctly.
If the photometric details were correct, you could change the rotation directly by selecting the Group.
Regarding your second question, the terms are not wrong, but they may have to be explained.
Mirror at X means that the mirror line is on the X-axis, but unfortunately it is not visible and therefore a bit difficult to understand.
Do not hesitate to contact me again for further questions.
Relux Informatik AG
Dear Basile Schlegel