Stroll along Sumida River
played
This one can be marked as completed. Good.
That was pretty neat. I was able to learn about the area and some words, too. I tried translating the poet's last words, but I guess it's a name.
The cartridge is a nice an easy concept and even includes some helpful messages should you stray and forget to take the key. However, for the yellow key section, upon returning and leaving again, I discovered this message repeats after I had used that key. Other than that, I don't see any problems.