(Or if you don't read Japanese)
MINASAN NO OKAGESAMADESU ~DAISUGOROKU TAIKAI
Mahjong games can be pretty frustrating if you don't understand them well enough, and Minasan with its unique board game quest offers even more potential confusion, so here we dissect its particulars.
By the way, the memory card DOES save your points & items in addition to position on the board, so don't be afraid to take a break.
For further help in mahjong in general, I recommend you consult both Nine Dragons (for general mahjong rules + Hongkong-specific ones, as well as a nice, proper 4-player piece of game software; don't miss page 2 of the scoring rules) in addition to Japanese Mahjong Scoring for an in-depth explanation which is Japanese-rule-oriented. Some of the Anglicized terms on that page might insult you, especially if you were indoctrinated into the world of Chinese mahjong, but the guide's usefulness speaks for itself.
Most importantly have fun! It's a tremendously addictive game once you get the hang of it.