I was too tired to post this last night, but TN released the second version of his HEN last night, 6.20TN-B. This fixes the problems with 04G PSP3000's, a few bugs, and allows downgrading. I will say though, although I've heard of people with 03G's successfully downgrading, I still think it is a very bad idea to try downgrading an unhackable PSP as you risk bricking.
You can get my new All-in-One package [here].
This package includes a trimmed down Patapon 2 demo from Omnija(only 49MB), HBL revision 109 and of course 6.20TN-B. It is set up so that all you need to do is run the exploit, and it will automatically run the HEN for you. Follow the instructions in the readme if you get lost.
On another note, later today I will be posting a review of Kingdom Hearts, and maybe Invizimals tomorrow.