I think that we are not understanding each other. The workaround you are pointing is not working for me. I did all steps you mentioned and still nothing. Or I understand this incorrect. I updated the product description and I can see that I have added 11 pictures. Saved it and go back to updating the stock - still nothing.
The funniest thing is that I want to update my stock only for 1 set because Iโm finishing with 2.1v shredder kit and starting with 3.3v shredder kit.