We have 2 extensions. one adds the option with quantities, one replace a product to option.
Now they work well without replace the product to the option with quantities.
The issue is in the cart.
We need the extensions work in 2 ways when the product replace an option:
1)with the normal option (without the quantity) : it is working well now.
2) with the option quantities : We ask to add this feature in the cart.
When I add an option quantity (it is an product), in the cart have insert the product with the quantity setted.
If you need further informations, I can give you a demo link.