I gave the new demo a try. Here are some things to keep in mind:

• I couldn't get past the second level - there seems to be an uncrossable chasm a little past the halfway point.
  
• On the world map, you can pass the first level without completing it (although I found the first level to be relatively easy by sspp03 standards, and I didn't have to abuse save states to survive).
  
• In 1-2, the collisions with the bricks and Ice Blocks are really glitchy - when I slide under a block to break it, I often get pushed down to the lower ledge, or even into the pit at the bottom. Example: https://dl.dropbox.com/s/s9j7tzq0i1csyo1/Mysterious%20Islandz_Glitch.png
  
• I think two overlapping Starman songs play while you're invincible.
  
• There's a lot of spelling and grammar mistakes.

If you're looking at a timeframe of 2-4 years for finishing the game, I applaud your ambition, and I'm glad you're sticking to one project instead of starting 20 new games every year that won't ever be finished, but be careful. People tend to get busier as they get older, especially if you go to college next year. More importantly, this game might feel very dated by the time you're done with it, especially since the engine is already four years old (I don't know how much you've modified CatY's 2010 engine, but judging from the glitches, I can recognize that it's the same thing I used when I started ROTW). I don't mean to discourage you - I'd love to see this game completed, and I certainly don't advise rushing development - but don't fall prey to the temptation to make the game as long as possible.

Did you play 1.1? The chasm is crossable in that update. And it doesn't matter if the engine is dated. As long as it is (the game) fun and challenging for others, its fine for me. And the glitches will be fixed in future releases. I assure you, this game will be completed. 2-4 years is a reasonable time frame considering I work on it on/off irregularly. BTW, I'm interested in forming a team.

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Edited by: TDW, Feb 3rd, 2014 @ 1:27 pm

I gave the latest version a try. I liked the unique level environments and novel level gimmicks you've used, although you might've gone overboard with the Bullet Bill cannons. Can Spin-Switch Castle be completed without hitting the Yellow Switch Palace? Is the switch palace accessible in the demo?

I noticed some more missing "mapblocker" objects on the world map: You can go straight north from Bully Underground to Spin-Switch Castle, and Boss Bass River is skippable.

The main problem with the engine is that it's glitchy. Mario can slide through slopes, and even though save states are enabled, artificial difficulty is never fun. Mysterious Islandz makes extensive use of Ice Blocks (a.k.a. Grab Blocks, etc.), and these objects simply don't work right - Mario's body protrudes about midway into the blocks when you stand next to them, for example. Since all of CatY's engines are similar to one another, you might be able to plug in some of his newer code to fix these glitches, if you don't want to figure out how to fix them on your own (if that's the case, I can't blame you, because his older engines are poorly documented).

The Yellow Switch Palace is accessible, but its in a level. As for the engine, going to agree on its documentation. I will use/modify his newer code, but I have to ensure compattability. Mikeystar was suggesting to recode the engine but I'm hesitant about that... considering the progress made already.
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Edited by: TDW, Feb 3rd, 2014 @ 4:11 pm

Just updated the first post with updated, more presentable information.

So after editing 1-4 to be Bullet Bill infested, I began making a new level. Its underwater, but much of the time, underwater levels in Mario games tend to be boring. What can I do to make them interesting?

I'm not sure I'd recommend adding more Bullet Bills to your game. You already have a lot of levels that use the "add as many Bullet Bill cannons as possible" trope.

As for making underwater levels more interesting, try thinking of underwater enemies, obstacles, or gimmicks from the official Mario games that were interesting but were never fully developed. Or you could try taking a common underwater enemy (like Cheep-Cheeps) and putting a new twist on them - make an enemy that's fast or that can chase Mario or even explode! Just a few random ideas.

http://s15.postimg.org/78286dkqz/Screen_Shot1255.png




For lack of a better alternative to the tiles used. The underwater tiles for the original SMB3 aren't going to fit for a grassy riverbed.

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Edited by: TDW, Mar 27th, 2014 @ 10:42 pm

http://www.sendspace.com/file/eb0kvm

Just letting you know this, this is not a true demo. Instead, its more of a test to see after I largely fixed the sliding collision with obj_slider when it comes to Mario being buried in the collision by one or more pixels, as well as making a few adjustment to Mario's masks and the main movement script "mariostep". I also noticed that the occasional stops in movement when climbing up the slope is due to the obj_solid placement below it.

However, I came into a new problem....when it comes to hitting the question and brick blocks...as well as trying to get the sliding pose's pixels touch the ground instead of being a pixel or two above the solid collision. I need your guys help to debug and fix the problem.

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Edited by: TDW, Apr 6th, 2014 @ 10:00 pm

http://postimg.org/gallery/5esiugec/