Okay, finally have a chance to try briefly.
The disk image in my originally link doesn't work with fMSX, I think it's because it is image of a different type of floppy drive than the ones baked into fMSX (which does not appear to be configurable). So instead I found a different disk image that has been tested to work with fMSX. The post above has been updated with link to the working disk image.
Also turns out it's not as straightforward as your typical console emulator to get the game running in the emulator, so below are some quick steps to get you started:
1) run fMSX
2) [optional but recommended] go to menu bar > Hardware > Joystick Socket 1 > Mouse to "connect" a mouse to the emulator. This only needs to be done once after which fMSX will appear to remember this setting on subsequent starts.
[aside: mouse doesn't work very well in the game at least on my computer, I think it might be an emulator issue. You can always play the game using just the keyboard.]
3) go to menu bar > File > Disk Drive A > Load Disk. This opens the usual "select a file to open" windows popup, where you can navigate to and select the disk image file to "insert" the "disk" to the emulator. This does need to be done every time you start fMSX as it does not seem to remember the previous setting and always start with no disks inserted.
4) now go to menu bar > Hardware > Reset Hardware to reboot. After the reboot the game should eventually launch automatically.
5) [optional but recommended] go to menu bar > Audio > Melodic MIDI Sound. This sets the sound emulation to play MIDI for all sounds. This is a workaround for a constant terrible background buzz you'd get from the game (though I suspect it may be more an emulation or emulator setup issue) if you set the sound emulation to other modes (besides the totally silent "No Sound" option). Setting it to MIDI does not actually get rid of the background buzz, but transforms it into something slightly more palatable to the ear while still leaving a semblance of sound effects to play.
The sound effects themselves, primitive as they are, seem to work okay, so it's unfortunate that you have this stupid background buzz sound laid over the working sound effects. This setting also persists on relaunch of the emuator.
6) [optional but recommended] go to menu bar > Video > Sleep When Inactive. This seems to pause the emulator whenever you switch out of its window to some other program. This is basically a workaround for the game not seeming to have a pause feature itself.
7) After the game boots, eventually you'll get to the game screen that asks you for mode of input and then the CPU, similar to how the DOS version asks you to select certain settings (eg. "IBM Compatible" vs "High Performance PC" mode) before going into the game proper. Using the keyboard, answer either "0" (keyboard) or "2" (mouse) for input mode, and "0" (Z80) for CPU.
8] The game's title screen loads with text prompting you to "PUSH SPACE KEY", so do that.
You'll start on level 1. There appears to be no methods witin the game to start from anywhere else.
The workaround would be to make use of emulator savestates (disclaimer: haven't tried those myself yet).
9) The in-game controls are somewhat primitive. The arrow keys or the mouse (depending on your selection of input mode per step 7) controls the cursor, which allows you to select the lemming to apply the currently selected skill to. However it does
not allow you to move the cursor down to the skills toolbar at the bottom of the screen. So to change the currently selected skill, use the ALT key on the keyboard (which still works even in mouse mode) or the mouse's right button. To apply the skill to the lemming under the cursor, use the SPACEBAR key on the keyboard (which still works even in mouse mode) or the mouse's left button.
9) There appears to be no options to pause or fast-forward the game, your best bet is to use the emulator's features for those. Holding down F9 fast-forwards the emulator. I have not yet found a way to pause the emulator other than the workaround mentioned in step 6. To end the level before number of remaining lemmings reach 0, simply nuke the level (the nuke button is found in the skills toolbar). The game does not seem to display the save requirement (or maybe I missed it), but there is one for each level, and text will be displayed at bottom of the screen whenever you've reached the requirement for the level.
Once you end the level, text will be displayed to either show you your score for the level (which I think is the number of lemmings saved or the percentage thereof?), or some try-again text if you fail to meet the save requirement. Either way you continue by pressing SPACEBAR on the keyboard (or maybe with the mouse left-button as well, not sure).
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That should be more than enough to get interested people started. I have to say, the sound and controls feel rather primitive even compared to other efforts like "Ant-Soldier", which really says something.
To be fair, some issues may be emulator-related; through this experience I'm not sure fMSX is that good of an emulator for MSX, but hey, at least the game is runnable in it.
