So yeah, played this today, and i must say not bad. I did find a few little niggles here and there (spoiler tag below), and some annoying problems, but overall it turned out quite well done in places.
The graphics were great i thought (in fact, the best part of the mod). It was always as though every scene you made had so many layers which obviously just means quality all round. My favorite scene (not for any big reason) has got to be the underground train with the little flies around the lights, such a good scene with the layers the train and what not. Most of your other scenes were just so good i don't need to mention them i don't think.
Music i thought was so-so. It may be fine and good in Shinobi itself, but i thought it was a little 'reserved' when it came to a beat'em-up. I also thought the music was a little quieter than it should have been, so maybe that's why i didn't really notice it that much to have a big impact on the mod as a whole.
The enemy placement i thought was the second-best thing in the mod. The placement in variety terms was right on the spot i thought, although there was the difficulty aspect....I didn't think it matched up right. I was playing on Hard and the difficulty on enemies alone was a tad high for me, but not really that high.......BUT THEN throw a deadly maze into the mix and scenes with potential life-sinks in the mix and oh boy, your mod is seriously hard for the difficulty IMO. I failed twice to make it through (1st time not my fault, see spoiler below). I also lost loads of lives in the "platform" scene, although I'm not complaining about this as it's a great scene.
The maze i thought was really well put together...in fact TOO well put together, I failed to escape it without looking at the path in Maker (I have a damn good reason why though in the spoiler below). To be honest, I like a maze stage, I really do, but yours is just too complex with too many punishments. I could definitely understand a rage-quit in that thing
The bonus levels were mixed for me. The clown one was great, but the seeker one i didn't like: All i got from this "Bonus" level was -1 life and a lost blitz. I can understand the bonus thing being about points, but hell, you get enough points kicking ass in the main story, so i don't really class that as a bonus. Bike bonus was good though, and i actually did well with that launcher.
The story:.....Ah, well...The cut-scene script speed was way faster than i was expecting to read it. 2.7 seconds per box just wasn't enough for me. 3.5 - 4.0 seconds (210-240 frames) is best IMO. I did though read the story back through the script files and liked it's simpleness to be honest. It worked very well, but just was delivered a little fast and shallow; Shallow meaning that you can spend ages going round in the maze and actually forget what it's all about, and having that many bonus levels can make the story shallow also.
Pros:
Graphics and scenes: Just awesome with so much quality in them.
Enemy Placement: Great use of the mooks and enemies, didn't feel random.
Story: Nice and simple, works well.
Music: Even though i said i thought it was so-so, I'll say "pro" because it is a Shinobi tribute and thus you couldn't have really used anything else.
Some bonus levels....are very clever.
Cons:
The maze: Too complex for my liking I'm afraid. The maze itself was very well done, just too well like I've said. If this was a little simpler it would have been great.
Script speed: Too fast at present for me.
Difficulty: Again, It's the maze's fault. The EP is a tad harder than expected but boy it shoots up with the maze involved.
Seeker "Bonus": Just not a bonus IMO.
Bugs and niggles:
1b Layer 9 needs setting to -240.
2a extro can be spoiled easy (My Max just exited through the fence). Change to Instant?
The water in the little pit in 2b overlaps the floor. Can be fixed with a little floor layer placement, although you have no more layer space and none of the existing ones share a descent z-axis I think.
The vertical wall/partition near the steel plungers in 2b could do with the C-map extending out a little due to a large overhang with the char (I was using Max)
Layer 5 in 2d can be got behind and made to look a little strange. C-map adjustment to stop this?
Music track 10 seems to skip on the loop
No special in stages that clearly are suitable (is this deliberate?)
Game-breaker/(-1 life): 3c Ninja was stuck in the crouched position over the pit in between the train cars. Looked at the level in Maker and looks fine, may have been random. The cause looks like when Ninjas are jumping around and falling in pits they might sometimes get bugged and stick. Killed myself to un-stick him.
C-map needs extending a little around the Container boxes in 4a (Char overhang)
No need for alternate route icon to scene 7 in 6f, scene 5 in 6o, and scene 13 in 8l.
In 6g, the middle door is the correct one. However, enemies drop just before it and infront of it in the "standing" position, and because there's no camera lock here, or alternate route activated when enemies are on screen you can fight past this door not ever knowing it was there, which happened to me which kinda gave me bad rage...I got killed and had a look in Maker at where i went wrong and then i found out why. I'd suggest adding a camera lock here to be fair.
Basically a Game-breaker: In 6h, the correct route cannot be accessed because there are enemies activated further down the screen preventing the alternate route. What makes this worse than a Game-breaker is that a person wouldn't notice it is a game-breaker until after they had been round in circles a few times. You can activate the enemies and bring them back to the door and then beat them, but damn that's complex thinking and I'd still call this a game-breaker for some people.
7c layer 3 needs changing to -240.
The last little platform in 7b is bugged, C-map needs to be looked at again here.
All in all, this is a fantastic showcase for a mod with the graphics and enemies, but it just needs some tweaking on other things at present. If you tweaked it, it would be a hell-of-a-lot better. So well done Ice! quality mod you have, and i really enjoyed playing it through bud
....Also, I never found the password in the game, although i did find it by accident elsewhere. Liked the "extra" snack

The box said "Requires Windows 95 or better." I can't understand why it won't work on my Linux computer.