Question 1:  I can print with the new ink refill, but I can't seem to reset the ink level warning for black. I have tried Canon forums and YouTube. The instructions on how to reset the printer are wrong because when I press the buttons, the printer just tries to scan. Makes me mad that I may have to buy another printer just to be able to use refillable cartridges properly.

Question 2:  I have a canon printer Pixma MG2950. I have tried to disable the "low ink" warning without success. When I follow the instructions on the internet they don't seem to apply to my printer. What can you suggest?

The answer to Question 1 & 2.

Keep printing.  You can't "reset" the chip.  Just keep printing until one day the printer stops you and says "Error 1688 (or 1686,...) the following cartridge is depleted.”  Do not close that window. Keep the window open and press and hold the STOP button for five seconds. The STOP button is the one with a red upside-down triangle, not the scan button.  You will hear a click, and the printer will get back to work. It won't track the cartridge ink level anymore, and you can add ink as many times as you want.

Question 3:  I would have let it deplete, but the refill guide said "do not let your cartridges deplete, you could damage the print head." but I guess I have no choice now.

The answer to Question 3:

By not letting the printhead/cartridge deplete, they mean the actual ink.  If you let the printhead run out of ink and print with an empty tank, you will damage the printhead.  This is different from what we mean by "deplete" here. Once you add ink, the printer won't know you added ink.  Therefore, you will have plenty of ink, but the printer will still show "low ink." You need to let the printer run to "depletion," at which point the printer thinks the ink is depleted, but the cartridge actually has plenty of ink.  Therefore, the printhead won't be damaged because you actually have ink in it, and the printer thinks the cartridge is depleted and gives you the choice of turning off the ink gauge. This choice is not available before the printer thinks the ink is depleted.  Therefore, you need to keep printing until the printer thinks it is depleted. During the process, if you see a color is missing or faded, you may need more ink in the cartridge. Always make sure the cartridge has ink in it and ignore the low ink warning until the printer shows a depletion window.  That will be your chance to reset (turning off the ink gauge).