In Single Player in the OC config there is an option "bufferChanges" set it to false. You'll find your programs in /MCDir/saves/savename/opencomputers/UUID/ UUID is the address of the hard drive that contains the files you want to edit.
[Also moved to proper subform]
What you need is the inventory_controller upgrade. This will allow robots, drones, and an equipped adapter block to manipulate and read external inventories.