The first day went well! I managed to fine some (appropriately retro) green lined fan-fold printer paper for a large map. So I scaled up my initial sketch for the first chunk of the game and added some annotations and some colour.
On the digital side, I installed a Tandy MC-10 emulator and ran some BASIC from text files. One little hitch is that the MC-10 is missing the INSTR command. Hopefully find a reasonable workaround.