Issue description
When an "Item Storage" has belts "In" and "Out" then "Keep Full does not work. What comes in goes straight out.
Expected behavior
i would expect the "Keep Full" to be adhered to
Reproduction steps
Place an "Item Storage"and store "Electronics"
Set "Keep Full" to 72
Feed the input with a belt (flat in my case)
Take the output with a belt (flat in my case)
You can see in my screenshot and save attached that items just left leaving zero instead of 72
Game version
Update 1 0.5.1a (202)
Attachments

Second.save
Files not imported: Second.save