Not sure if it's the stackers or what but as you can see splitting off the space belt and having some of the input shape bypass the stackers makes the outputs think the bottom item is going on the top and bottom.
#[0.1.0-pre8-rc1] Bypassing my stacker gives incorrect predicted shape.
red sluice
Appologier the poor quality, I just downloaded the first screen recorder I could find lol.