Why do you need Physics here? You should avoid using Physics with Platform, Solid and other behaviors, it can cause all kinds of problems. This is clearly a platformer game, you should remove Physics. If you only need it to "freeze" dead enemies, you can simply disable Platform behavior.
Also, you have some logic problems in the code, I didn't check everything, but events like "Enemy Health<=0, Trigger once" are wrong. Trigger once doesn't work per instance. If one instance has Health<=0, then this event will not be executed for other killed enemy instances.
Since you are disabling collisions, you can change this event like this:
Enemy Health<=0
Enemy collisions enabled
.......Enemy disable collisions
.......Enemy disable Platform
.......Enemy Set animation to "Death"
........
Same with Player sprites.
Besides, there is a mess with collision polygons in your animations. They all are different sizes and shapes. As a result, when animations are playing, collision and overlapping checks will not work correctly, on one frame player may overlap an enemy/obstacle, on another frame not.. It's recommended to use an invisible sprite with Platform behavior, with a single frame and rectangular collision polygon. And then you pin your animated player/enemy object to that sprite (like skins).