Red and Green sliders should work together on storages.

Don't see why I can't decide the storage can't be full or empty at the same time.

There are valid use cases for such a scenario.
One example would be an animal feed storage with belts in and belts out. If the belts in aren't providing enough, it could be useful to import animal feed from elsewhere. If the belts out aren't consuming enough, it could be a source for other storages (e.g. sending it off to boilers).

all the conditional checks on the sliders should be inclusive. >= or <=