Attaching an extractor to a double-wide chest don't pull items from the far side, it doesn't treat the inventory as one, but rather as two separate containers.

Minecraft 1.14.4
Forge 28.1.34
Create 0.1.1

This doesn't work, but I think it should.

actually, upon further testing, it appears to be an issue with the belt funnel.
If I put items in the chest manually, it comes out the extractor. but, if the belt funnel picks them up, they stay in the chest.

The problem here is that the chests inventory does not notify both sides when it's contents are changed by other blocks. (Funnel, Hopper, other pipes).
The extractor doesn't ask the chest for it's contents every tick, instead it waits for the block to expose a change to the inventory. The same mechanic is used by redstone comparators for example.

This should be addressed in the new version that went live just now.
Thanks for the Issue and feel free to re-open if need be.