Checking with the backend team to see what is going on.
One note from them though is to convert the video you are uploading to Starlight to a H264 mp4 format file with yuv420 as the color space to eliminate issues with processing.
Came across this thread when I hit the same error, running windows 10 on a pc. Converted my 10 second clip to an h264 mp4 but still no luck. Finally got it to work by converting the original video to progressive (source clip was interlaced with upper field first) which triggered the read error I presume. Hope this helps!