Assign multiple products to one supplier. Cant believe this isn't an option now!

I was surprised to find out this cant be done. We weird thing is it can be done but it doesn't "take" after you post data to web. You can use mass product changer to change supplier on multiple products but when you post data to web its doesnt change in the PS BO??? So im not sure why the option is even there. It was explained to me that the only way to do this is when you originally import the products via csv. Here is my original ticket to show you exactly what I tried to do and it not working:

When I use store manager to assign a product a supplier it doesnt update my presatshop back and thus doesnt update my site after i post the changes to the web. And when i go and get data from the web it wipes out all the changes i made assigning all the products to the correct suppliers. Here are screen shots to show you. Here is within store manager where its shows I have products assigned to a supplier:

http://prntscr.com/2lxu6h

http://prntscr.com/2lxv3j

And I posted these changes to the web and as you can see no changes:

http://prntscr.com/2lxvmj