Given a RenderWindow.Channel opened with RenderWindow.StandardChannels.RGB, a subsequent call to Channel.SetValues in RhinoCommon 6.24.20079.23341 expects a buffer of float4, while when run under RhinoCommon 7.0.20091.15085 it is read (as expected, I guess) as a buffer of float3.
@jdhill thanks for the report. I created https://mcneel.myjetbrains.com/youtrack/issue/RH-57751 to track the progress.
I never noticed this change with Cycles integration, as I always use RGBA channel for writing.
Thanks Nathan, my workaround will indeed be to switch to the RGBA channel, just reported to let you guys know.