So the way it ought to work is if you add a sprite with shared pallete off any sprite added directly after that one should share palette with it. However some people mess that up and if its an old character mcm 2.0 guaranteed to make it awful.
You ought to be able to fix it by turning OFF shared palette for all the FX rather than turning it on.
Are you actually using a projectile sctrl? Projectiles still use pausetime. You want to reduce ghat value for the projectile to make sure the animation continues. Use projmisstime to split up the hits. Use projhits to limit it to 5 hits. Do all the normal hitdef stuff so it pushes right. If you don't give it a velocity it will remain in place.
Wrong colour bg for making that particular effect look pretty in mugen. You need black tbh so the transparency stuff actually goes see through round the detail. Right now your effect will retain a green tinge around it even with trans = add in play.
Any mugen sprite not using alpha transparency needs a 256 colour palette. Colour 0 which is top left or bottom right depending on application will be your invisible colour. Most of the time if the image has pure black that tends to be 0 by default which is good for your purposes. All you have to do is add it to the file with shared palette turned off and you're good.
Re: Adding blue boxes to a char leads to error and game crashing.
Only via creating your own frontend. That way you can reference whatever you like as the match is called via command line letting you specify characters and stage. Otherwise font is as good as you get in normal mugen.
You can set up a mash command and have that trigger to break out of the light punch. Allowing it to happen within its own state as well allows you to keep it going.
Command = a,a,a,a Time = 5 For example should net mashing the button. Use that in your changestates and you ought to get something. If you do use a variable its to limit the number of times you can use the attack in a row.
If you define attacks as 0 juggle points in the cns or even set the constants value to something high you'll combo without any limits. Thats the easiest option. If you want limits in play your 1st step is working out what those limits are and how they should act.
Re: Is it possible to make a char immune to guard break/crush? If so, how?
Custom state detection. If someone inrlicts guardcrush you will most likely be in a custom state. You can set yourself up to break the guardcrush state if your state doesn't match a variable and your prevstateno was any of the guard states.
I think custom state detection is in the code library
Re: A few questions about what defines a compilation or fullgame
Sprite styling also becomes important. So same style portraits. If even one character has quotes they al should. They share hitsparks. They share hit sounds and any super activation fx/sounds. The system needs to be the same across the board.
The only thing that can be different is the characters and what moves they have. Normally the sprite style should be the same too. Like don't mix VS with kof with garou. But thats not totally set in stone. Just preferable.
Basic mechanics must match. Common fx and sounds must match. Systems must match. If any of those are left out I'd be leaning towards compilation still.