Well, like you said, the translation is really incomplete. At least with it, I can see how powerfull it is, and I have to tell yah, it's really VERY powerfull
From what I got so far, you can make stages that scroll to whatever direction you may like (thus, you can make horizontal ala R-Type, vertical ala Swiv or even Diagonal ala Zaxxon), and I also think you can change the direction of the scroll in the middle of a stage (Not sure yet). I believe you can also make a game ala Alien Breed, but I am not sure about that too.
You can have 4 different layers of backgrounds in each stage, each one independent to each other (I.E., it can scroll to any direction or speed).
You can have 8 different ships for your game, with different power-ups for each one. I still don't know how the power-ups work, but there's an image that looks like the Nemesis power-up bar, so at least this mode should be supported.
You can make an opening sequence for your game (Have you ever seen the Aleste 2 opening sequence? You can do something like that, put a bitmap on screen, show some text, then change the bitmap, and so no), and also add cut-scenes between the stages (Done in the same way as the opening sequence), and also, of course, ending.
You can also make a "Continue yes/no?" screen.
In the music department, you can use only .MIDs and .WAVs.
I haven't seen an option for 2 players game yet (That would be fantastic).
I still couldn't make my ship shoot (Yeah, stupid
I also couldn't add any enemies yet...
The biggest problem so far, is that the program has 255 different events that can be added in the stages (Stuff like change the BGM or setup a change of scrolling speed), and this whole part isn't translated yet, so figuring out what each event does, and how it works, will take a LONG time
I don't know if the version I have will be too big for the zone. If it's small enough, I'll post it there..
Edit: It's in the zone, I removed the .WAV files for size sake. Maybe you'll need to create .wav folder inside the ShooterMaker folder to make it work...