I love madness tributes
Probably because they are the only thing I can make and since I am bad at it I feel mean for giving critisism but screw it I am more of a critic.
Heres your fine points
-Good frame-rate
-Some non sprite sheet objects(big plus from me because I cant draw)
-Good walkcycles(Tweened though, see negatives)
-Good effort, it didn't seem like something you tried to rush
Negatives (I feel hypocracy setting in)
The tweened walkcycles, although were good, but when you use them in that fasion they seem over done, there wasn't much action or any real activity, it was just them scrolling the screen, in my opinion, if you're going to use tweened walksequences, at least use them along side with something that draws your eye away from their movement, such as having other things happening on screen other then just scrolling. I would recommend though not using them because although they are easy, they add a mundane and unrealistic feel to a flash, especially yours which seems to be a horror type setting, people would move with more emotion such as larger steps and maybe some panning around the area instead of just looking straight forward while walking.
I understand how it is an episodic movie and I am fine with that, but there needed to be action. I originally typed a long rant about how there wasn't any but I noticed it was after credits so I just deleted about 300 characters so now I can discuss your action sequence. First though, you should have had the action in the body of the flash, because I would have over looked that. The action is what drives the madness series and should it's tributes unless you are going for tribute that only uses madness characters but in a non-violent way. Regardless, the action needed to be more prominent.
Analysis of the action: My biggest pet peeve about madness tributes is the subtle things that get over looked that make Krinkel's work amazing, those are the blood sprays, bullet casings, and the movement and emotion during and after combat. You lacked the big blood sprays that make the flash more gritty and madness like. You also missed the bullet casings from the gun, which are a pain to animate but add more realism to the movie. Also as a side note, increase the recoil of the weapons, add tracers that last about 3 frames to show where the bullets are going because I just saw a blast and then like 5 bullet holes appear. Also, when moving characters in combat, try to slant their feet to make them look like they are gripping the ground because people don't walk flat footed, if you examine Krinkel's movement he has his characters shuffle more then just take steps. When in combat, try to show staggered, more worried or frantic foot steps, even by the protagonists. Have boddies tilt back and maybe be pushed back when fireing weapons, I recommend pivoting the torso on an axis at the bottom. This adds more realism because recoil doesnt just move hands, it moves the entire body back. And finally, I don't know what the bad guys were supposed to be, zombies or hybrids or w/e but unless they are blood filled robots they are going to stagger when hit, not just plop straight down unless they are completely blown away. Have them fall in more of a struggled fasion and maybe allow them to struggle once they are down, instead of just drop and lay flat, or crawl with their hands to be shot again to be finished.
Finally the audio, Audio is hard to find for madness movies, or at least it is for me, but at make sure there is more dynamic sound effects when there is no action, such as their panning movement, try adding some ambient noises or footsteps maybe. And the gunsounds were rushed when the gun was fired, you need to give more frames between shots because it was extremely rushed and brief.
All in all, a promising start for a possible greatness.
Oh and I almost forgot, add car sound effects if you are going to have a tween car scene, but I would avoid them all together :D
Holy crap, I only have 20 characters remaining in this review, sorry for the long one.