I use a mix of cheap cooking spray (aka PAM), mixed with denatured alcohol. The spray is $2.99 for a 16 oz. spray can at the restaurant supply store, and the denatured alcohol was $13.99 for a gallon, which will last forever. I spray as much cooking spray as I can into a pint spray bottle, which won't be a whole lot, due to the foaming action. Then I fill the bottle the rest of the way with denatured alcohol and shake well. As the level goes down in the bottle from use, I'll squirt a little more of the cooking spray in and shake it up.
In use, I only spray the molds while they've got bullets in the cavities, which cuts down on the amount that gets in the cavities and causes wrinkles. You can stop the carriage just where the sprue normally falls off for each mold and give it a quick spray. Don't over spray!
I don't use anything in the mold cavities themselves, but then my machine has knockers, which work pretty well. I'll still get a bullet sticking in the cavity every once in awhile and have to stop the machine and get it out, but it's rare once the molds are broken in well.
Hope this helps.
Fred
PS: The cooking spray smells like fried chicken cooking.......