The route has not been walked. The gates come from the table at p09:A269 and from the lists of things; we have not gone through a torii in openMSX.
Area 0x18. Gates 14-17 lead to it, and it is in none of the 24-area tables. No list of things places those gates.
How the game ends. The stage-6 room asks for five heart jewels (see Findings): where they are and what happens when you carry them has not been measured. Rooms 3, 5 and 6 send you back to stages already crossed; what decides the ending has not been read yet (state 12 is set by 0xC4DA, written by ENDDEMOGAMITAINA and by someone else).
METALSLAVE: it was typed while Gao was dying and could not be measured; the code (p06:B92E) sets energy 0xC845 to 200.
The STOP key with Q*bert or the Game Master next to it: from the code, not tried.
The enemies' colour. The sprites of the sets are in two tones: the colour is set by the code of each type and has not been worked out type by type.
The unused version of five bosses (p07:7457, p08:82B3): whether it is an earlier drawing, and what the other two figures were.
Items 18 to 32 are drawn with nearly empty icons from the sheet of the dumped stages; their icons may be uploaded at another moment.