If you need some help with the Designer's Delight Trophy to make it more easier.
If you are just left with chests, you can go to world 283-935-56 G and you can get to 5 chests, delete the world and re-create it.
This won't take too long to get it.
You can view my video to see where all 5 chests are.
Once most of the items are found in chests, you will start getting weapons/items. You can still get the required items after that.
Thanks
Killarpong