I'm unsure what you're referring to when you mention a movement bug. If it's slope jumps, that's an intended mechanic. I sprinkled several optional paths in the earlier levels to give players the opportunity to discover the mechanic before requiring it to progress in the Mountain stage. I intended to add a sign at the base of that particular climb to signal the need to slope jump... but then I forgot.
The wolves are faster than you, but less agile. They stall for a bit just before they jump (from .25 to .6 seconds depending on difficulty). You can use this to juke the wolves by stalling their momentum, or causing them to miss a jump, or creating an opening for you to dodge around them. Most locations have either jump-through platforms, cliffs, or slope jumps you can use to your advantage here.
When it comes to struggling, the most effective method (that I'm aware of) is to wait for the cursor to turn white, then push as the cursor crosses the middle line. By doing this you can escape the wolf's belly going from 100 to around 87 health on difficulty level 1. I was a bit unsure how much of this to communicate to the player. My thinking was that I wanted the player to be able to discover the best way to struggle on their own, so in the instructions, I decided to be a bit vague, mentioning only the fact that you need to build momentum. I might see about being a bit more explicit about this in a future update.