Would it be okay to remove the invisible shield after it's been drying for 4 hours? It seems there are lot's of bubbles on it but I've ran out of the "special solution" that you're supposed to spray on it.
I'm not so sure about that... you dont' really need the special sauce to apply the solution, but after letting it dry that long i think it might remove the adhesive. Are the bubbles air or water? If they're water, don't worry... they somehow, magically dry out. I have no idea how. But they do. If they're air, then i don't know what to suggest.
What you can do is make "wet water" (as it's known in hobbyist circles )
again, from their site:
Make a solution of soapy water. Mix 5 to 10 ounces of water with one small drop of liquid baby shampoo or liquid dish soap. Please note that you will NOT be needing all of this water. In fact, you will need hardly any of it! It activates the adhesive and makes the film slippery when applied.