sure they do.. as stated in the NEW TRAINER with the NEW INSTRUCTIONS, you must ALREADY HAVE SOME OF THE ITEM (i.e. ammo), then you turn the option on, then when you go to USE the item, it won't subtract any. I've tested it with multiple game saves sent to me from multiple people.
the only possibly problem is the green gel for some people, but I have not been able to narrow down why. Since it increases the amount when you press the key.
if neither trainer work I have no suggestions for you. It is tested working here with multiple saves sent to me. especially the second trainer.
Glad you enjoyed the vid, I certainly enjoyed making it, Cal's work is superb!