I currently have 2 strange results from using the stretched billboard:
If I reduce my start speed to zero, stretched billboard particles won’t show up.
Stretched billboard ignores start rotation setting.
As soon as I switch this particle system back to regular billboard both properties are recognized.
Very often things that seem like bugs are just features I don’t understand, so perhaps there is some other way people know to set the start rotation or have a start speed of zero for a stretched billboard?
Hey, Stretched particles take on the rotation of their travel, so if they aren’t moving they have no direction so they don’t show up. And because they take on rotation of direction, you can’t modify their rotations.