The game requires true drive emulation on the TheC64. Just rename the file to "mineshaftgap_AD.d64" and the emulator will use this mode. The downside is, that the game load times are much longer. You can solve this problem by saving a game state on the intro page, and for all future runs just load this game state.
It works fine on my C128 and on Vice in true drive and iec mode, but I can reproduce the issue on my TheC64. I will let you know, once I find the problem.
I just verified again, that it is working by using a vice screen recording. Without overtime the fuel tank lasts for 15 seconds and with overtime for 30 seconds. So it seems to work.
If you can't build a mine, you have run out of metal. The building menu shows the resources required for each building. If the building is shown in red, you have a lack of resources, if it is blue you have not researched it yet.
The top floor has infinite oxygen, so the oxygen meter starts with the second floor. Thank you for the bug report, I will look into the menu reset issues later to day.
Having no native hardware split screen options on a C64 one is kind of limited on the art side, when trying to do smooth scrolling with an independent left and right display.
A cartridge version with cut scenes, more graphics, multi SID support, story, more units, multiplayer etc. would be an option, it this genre should resonate with a big enough C64 crowd
You have to destroy the sentinels orbiting the artifact before you can collect it - which might be tricky because you don't want to shoot the artifact, and those sentinels have the ability to respawn as long as one of 'em is still in business.
The first galaxies are rather easy, but believe me, it does get harder if you progress - and yes, the bounty does also increase. And don't forget, all the money you spend, will be back with you in the next live.
Pin 5 and pin 9 (paddle inputs) are mapped as joystick button 2 and 3 ... I don't know which is which, I tested this on Vice, but I was told it works fine on actual hardware.
There is a trader artifact, that you can use to summon a trader without the need to search for one. If you look into the galactic map, you can at least see, which systems have the down gate.
If you collect enough Wormhole artifacts, you can jump to the last galaxy right at the start - summon a trader or two with the trader artifact, and use scanner artifact to breeze through the last galaxy.
