So I have running down, it's just getting back up after a landing and getting back into running that I'm stuck with. I'm doing some parkour training maps and so far that's a critical issue I have that I'd like to fix, any tips or guidance?

What about posting some replays to let us figure out what is happening and how to help you ?

General advice would be to plan your previous moves so that you get back on your feet from them, while keeping balance. To return to a run you usually wanna get as close to typical running position as possible or that pre first step position if you don't have momentum build up. Then you should be able to use similar moves you usually do when running/ starting a run.

Being rotated towards direction you want to run to would be ideal too. If you're flying to different direction than you want to continue to run to, it complicates things slightly more, since you likely need to stop that momentum to wrong direction before starting to run.

This is something that can't really be "taught" to someone. The only way to do this is to get better at balancing the center of your body. Along with hours of trial and error.