if I load scenes from Rhino5|VfR2 projects at Rhino5|VfR4 now, than the lights are gone. Strange, if a use the commad _selall than Rhino told me the lights are selected … but they are not visible. Here an example file. Copy and paste from Rhino5 task to Rhino6 task works.
Thank you for reporting this and for the provided file! The issue has been logged for investigation.
The issue is that when the .3dm file is accessed via “File > Open” the Rectangle lights’ size is not read correctly and instead a default size is used(2,2). The lights are still there, but are simply too small to notice.
There are a couple of workarounds to this issue.
You could double click on the file, right click and open or import the file through Rhino’s menu > File > Import.
Additionally, you could go through the lights and enter their previous size values manually since their positions are preserved correctly.