Funny quote out of Wikipedia regarding Teenage Mutant Hero Turtles:
A series of computer ports were developed and rushed out in time for that year's Christmas season, but did not fare nearly as well, commercially or critically. Despite the fact that this game was a success, it got many mixed reviews. The game received criticism for its difficult gameplay, being noted by many fans and critics as being one of the more frustrating NES games made. However, the computer versions were even harder due to sloppy programming and controls.
Knowing the conditions they were done under.. no wonder!
Pretty amazing you pulled those 2 off in 2 months. Hell I didn't even knew there was a ninja turtles game for the Atari ST (owned one back then.. was also coding but it was BBS door games in GFA Basic). I thought Konami never did a game for the ST. Learn something new every day.