Reginleif, what you speak of is called an afterimage. While that's not inherently spiritual, it can be as well as the same colors and shapes can be further developed for visions. When you get more into those, you experience closed eye hallucinations more associated with altered states of consciousness.
Atomspliter, your problem isn't that you need to "unlock" your aura, but that you need to get used to working with it. When I tried to focus my energy through my body, it was really hard for me because I was concentrating on "moving a small muscle really hard" rather than using all of my muscles to move my body, so to speak; I wasn't letting my energy flow properly. Once I let go of concentrating or focusing too hard, energy work became a lot easier for me.