There is no manga for the game Project Diva. However, there is a manga based on the same characters as Project Diva called Hatsune Mix.
You have to have the original Project Diva and a PSP with the game in it connected via USB to a PS3 with the software installed to play Project Diva Dreamy Theater.
yes
No Japanese PSP game
You can buy it at Playasia.com
Pause the game and select either "Save and continue" to save your progress and keep playing or "Save and quit" to save your progress and stop playing.
you're able to get a free download of project diva on 4shared, but you would have to make a free account. I just downloaded mine and it's just amazing.
Project diva one has songs mostly featuring Miku. There are only about 4 len/rin cover songs on there. Also most of the models are Miku. In PD2, They focus on Luka, miku and len/rin. Also, the arrows and a "hold" not was added.
On the file menu click Save Project or Save Project as... When saving a project make sure you save the forms on the project. So that when you open the project the forms will open also.
You have to buy the full 1 dollar game to save your progress
Search it online
Sadly, no there is not. It's only made for PS3 and PSP.