Hi, Saverio.
I'm afraid I'm not interested in porting the game to SG-1000: code relies on MSX BIOS and requires 8KB of RAM, plus a new soundtrack must be composed. I am already involved into new projects (that are taking too long to be finished), and I don't really want to put them on hold to go back to Stevedore.
I'm sorry this is not the answer you were expecting :/ I wish I had enough free time to be able to finish my projects and also experiment with new platforms (such as SG-1000)...