The debugging aspect of Star Ocean: The Second Story is mad... I knew this game was legendarily problematic to hack because of its readiness to shift memory around, and that getting to the debug room involved activating a flag option on the debug menu, then entering a certain town in the game. It turns out that with 'SFLAG' up, trying to enter certain areas in the game can result in seeing other areas, though not necessarily with a controllable or a visible party—and what you get can depend on other flags and where you enter from; trying to enter the main area of Arlia from the left, at different stages of the game, I've been presented with both a bakery and a hallway. Trying to turn Lacour into the debug room is trickier than the FAQs make out; I got sent to several other places, including the middle of the ocean. (Rena didn't drown, but she couldn't walk either.) I eventually got in when I tried the Private Action mode.
As for the room itself... well, you're invisible. Rena's sprite is buffered, but isn't drawn in the actual room. (Incidentally, in the bottom right of the buffer is the part of Lacour one would have entered in normal circumstances.) There's a background image but it's just a backdrop. Other than that it's a nice, functional debug room; apart from the version details nothing seems to have been attended to in the translation, but at least the translated game can still display Japanese script correctly.