I'm also having some trouble installing BE. I tried several times before reapplying the stock theme, then downloaded and reinstalled Stock, followed by trying again to install BE, but no luck. Recovery tells me each time that the installation was successful, but no dice. I've wiped cache before each attempt, also.
Any thoughts?
You're running the P3 kernel from the Sapphire page. It has dev code in it and fills your /system so you cannot theme. That's my one thought.