It only seems to happen when multiple shapes from different trains are being unloaded to the same unloader.
While the first shape is unloading, if a second different shape is then unloaded to the station, from a different train, the unloader only seems to unload the first shape to the belts despite what the second shape is.
It also still only shows the first shape in the unloader progress bars, even though a different shape has been unloaded and all of the crates are no longer visible.
#[v0.1.1] Unloader unloads 2nd shape as the first shape
2 messages · Page 1 of 1 (latest)
Some packages are hidden inside the unloader - it has an area with a solid top where the packages go in, you can't see them, but they are there, being processed one by one. Maybe you just didn't wait enough for the new shape packages to reach the unloading point and actually start unloading?