Are versions for Color Computer or Dragon planned?
Breaks my heart to say no at this point. But that has nothing to do with the computers itself. I chose to go for the Z-machine version 5 with Ghosts, or XZIP as Infocom used to call it, purely to create better and bigger games and work around the many limitations that come with z3. The CoCo is unfortunately one of the very few computers still out there where no Z-machine version 5 interpreter is available. But I know you're good connected and the CoCo community is super big... the sources of the Infocom interpreters have recently been published. If someone on the CoCo Discord for example is capable to make the interpreter work with z5, I'd be more than happy to add CoCo to the list of supported systems https://github.com/erkyrath/infocom-zcode-terps
That would rule out all the machines not CoCo3, I am not sure if this is the right way to approach the matter, especially since the Z-machine interpreter sources are published now. Someone modified the Atari 8-bit interpreter as well, which lacked z5 for a long time. I am also not sure how many people in the CoCo world actually run Fuzix. Let's say there are options. If someone is able to help me getting the game running with a reasonable target audience on CoCo machines, and with reasonable I mean making it work for most of the CoCo users, I'd be more than happy.
It's definitely better done by porting it to DECB (Disk Basic) which shouldn't be too hard for someone who knows the platform properly. I was just presenting a pointer for the moment. fweeplet is derived from fweep so it's C and portable which is always handy. DECB is alas not my area of expertise so it would nee dsomeone who can replace the I/O routines and disk open/close/read/write stuff.