Developer Page: Japan Art Media
(dev id no. 15 - prev next)
Primarily an RPG developer, having worked on such things as the Aretha series and Lunar Legend for the GBA. According to Wikipedia they developed Lunar Genesis as well, which is widely regarded to be the worst in the series. Ah well. The Party Sugoroku seems to be their only contribution to the Simple series and their sole PS2 game, but the works page on their website hasn't been updated in a while. So I can't be sure.
Official Site: http://www.jam1989.co.jp
Simple 2000 Series
The Party Sugoroku (Twenty 2 Party)
Simple DS Series
Atama no Ikunaru: The Me no Training, The Hikyou Tankentai ~Choujou Special: Kyoui! Jinrui Mitou no Sekaikakuchi ni Nazo no Mikakuninseibutsu ha Sanzaishita!!~