Just for fun and maybe to find out a bit more about pirating history, I started having a closer look at this game.
Currently six different ROMs of this game are known. I visually compared them and found some (slightly) interesting details which may allow to draw some conclusions.
Four versions (called Open Sesame) display an initial screen with some digitized voice. Here the screenshots of the three PAL versions are 100% identical, but the NTSC version by CCE shows a nice rainbow at the top. Where the PAL versions constantly store the same color value over and over again, the NTSC rainbow is created by some (simple) additional code. Due to the different color ordering, this simple code wouldn't work well with PAL. The bottom parts of all four versions show a rainbow (again). Here the CCE version simply uses a counter for the color value, while the PAL versions add a constant ($90) to the counter before storing the color. Without the constant added, the bottom two color blocks would both be grey.
So, what's more likely here? The NTSC developer realized that he could add a nice rainbow to the top too? Or the PAL developer fixed the code not working for PAL? I think the former is correct. The 3rd screenshot shows the NTSC version displayed in PAL colors.
Now for the actual game screens.
At first glance, the three PAL versions of Open Sesame all look the same. But there are some small differences.
- The boss at the top in one Goliath and the BitCorp version has doubled scan lines, in the other Goliath version it is displayed with single line resolution like all three NTSC versions.
- The bottom rows of all three PAL versions show doubled scan lines again. Those do not fit to the platform display above and especially to the player's character. Also notice the missing feet and the tearing!
- The score is displayed in yellow in all NTSC versions. In all PAL versions, the top score is grey (using $1C as color value, which is yellow in NTSC and identical to the NTSC versions). Two PAL versions color the bottom score.
For me this looks like NTSC was converted to PAL.
Now let's compare the three NTSC versions:
- Most obvious is the changed boss. And while the apple is animated the other boss is not (to gain space for the digitized voice?)
- There is an extra white line at the bottom platform in the apple versions
- Both apple versions play a little tune at the beginning
- The copyright disappears after the initial tune is over (this does not happen in the other four versions).
The two CCE versions also show some differences:
- The platform colors differ slightly.
- The bottom color differs too
- The CCE apple version has the same colors as the ZiMAG version.
Now my (speculative!) conclusion summary:
- I want my Mommy from ZiMAG is probably the original version.
- Then CCE hacked this version into their NTSC apple version .
- Based either on the original source code or a disassembly, some other NTSC (CCE?) developer added the digitized voice (they removed e.g. animation, initial tune and white bottom line to gain space) and changed the boss.
To be honest, I have no clue while some colors where changed between apple and digitized voice NTSC versions.
- The NTSC version from CCE is the most original digitized voice version, but maybe based on some yet unknown version.
- All PAL versions are based on the CCE code, they doubled some scan lines to fill the larger screen better.
Of course this is all just speculation, but the (often subtle) differences between the versions make this one most probably.