There's some fun stuff in here! A few suggestions....
I liked:
-creature getting hit by a car
-Shooting a gun, punching, running (although you could have exaggerated the movement a bit for the run)
-Robot run and box push (why did a number flash in this section though?)
Needs a bit of work:
-ballie on a pole... nice ideas, but a bit too snappy/fast for me
-creature running... I'm not sure what you referenced... dogs running or cheetahs or whatever, but the hind legs look like they go way off to the side. I think there are a few pops in the hind legs as well. You should also try to curve the spine more (do reversals in the spine) to get a feeling of power... right now it's kind of straight (look at the side view)... (if you had frame numbers I'd tell you what frame to look at...) but There's one part that really shows this in particular... it's from a hind 3/4 view and its butt is way high in the air... at this stage in the stride, the spine should have a C curve towards the ground, not flat.... I see weird popping or arcs from the hind view (in the hind legs)
-The slidey doors anim is a good idea, but your camera placement makes it hard to see what's going on-- you never realy see him get his body part stuck in the door... it always occurs in a camera cut
Hope that helps! Post more animations when you get a chance!!! I like your stuff
~Mechis
ps. If the creature stuff doesn't make sense, ask questions and I'll see if I can explain myself better. Also, it would help if you posted up a version with frame numbers.
I just had a thought-- you should rent the Alien movies. I forget which one (one of the sequels) had an alien that ran on all fours, like a dog. I bet that would be awesome reference...