Here's a bit more information.
David wrote:I wonder which port is it...
It is the port for the Game Boy Color (GBC).
Tomorrow, 2 November, I will release a mod of that port.
The mod uses only 1 room per level.
(Plus, now and then, a closed-off room to the left, to make it seem as if the prince arrived from there.)
The majority of the rooms incorporate something unique to the GBC port.
Next Monday, 7 November, I will release the level editor.
Its GUI is virtually identical to that of apoplexy.
There are, however, several differences.
For example, the port ignores - they do exist - event numbers of raise and drop buttons, and uses a separate list.
This means there are about 5 days between the release of the mod and the level editor.
The idea is that this turns the mod into a 5 day challenge.
How many levels can people finish before the editor arrives...
The levels are not hard and do not contain difficult tricks.
Several levels are (much) easier to finish once the level editor is available as an inspection tool.
In theory, there is enough time for someone to figure out the compression algorithm.
(Especially with the availability of both the original port and a mod.)
In practice, now that the arrival of an editor is so close, why would anyone bother.
A couple of days from now I'll write a bit more about the differences between the DOS and GBC ports.
Then I will also explain why I picked the GBC port and which coding challenges I faced and how I tackled them.