I'm sorry to hear you're experiencing a cartridge error.
By "paper shim" do you mean you added a wedge of paper to the bottom of the cartridge to push it up, or to the side of the cartridge to push it over?
Please try pushing carts to the left, as per the instructions below:
With both cartridge bay doors open and all refillable cartridges locked into the printer: push all cartridges towards the left, so the bottom/left corner of each cartridge is touching the left edge of the railings in the cartridge chamber. Close the two bay doors, and the printer should then read the chips and pressurize the cartridges. At this time, check the LCD panel to see if all cartridges are correctly recognized by the printer (no error message).
Please let me know your results, if you have questions, or if there's anything else I can help you with.
Best regards~ Dana