It seems like tagging is completely broken. It doesn't matter which version of Construct I use, it just never works. I tagged my stopped animations as stopped and my walking animations as walking and it does nothing.
So, instead I set it so the events trigger the animations.
I finally managed to get everything running smoothly as possible with the correct animations playing and everything and now I've run into another problem.
When pressing diagonals (up/right, up/left, down/right, or down/left) the running animation plays fine, yet when it stops, it doesn't play the diagonal stopped animation.
Instead, it uses only the up, down, left, or right stopped animations.
I don't want to make it so the player can only face diagonals while moving as that will make combat really annoying (I might turn this into a Zelda-like engine).
Here is the cap file (uses the latest unstable build (by accident really, whoops)):
As you can see, when you move diagonally, you can't really stop diagonally.
If anyone knows how to fix this, I would appreciate it.