The registration room is A46b. It is on level 4 of building 本館, which can be found here http://www.otemae.ac.jp/about/campus/sakura.html.
From the main entrance, please take the first flight of stairs you see. There will be signs and a person there to help, if needed.
A visit to the Tezuka Osamu Manga Museum
Drumming and a laughing good time at Open Campus