I see, but nothing is impossible...
Someone managed to reverse-engineer other spectrum games, maybe it's possible for The Sentinel as well.
The almost-3d engine could be taken from the freeware clone "the Sentry" (maybe), but the unique algorithm that generates the 10000 levels has to be the original I suppose.
The pc version runs fine an very old machines such as 486 66mhz, so the easiest way to see this game on our Dingoos is the Dosbox way.