In order to complete a long range attack, you really have to first establish forward momentum (in the direction of uke) as fast as possible. Once you are moving forward, it's just a matter of keeping yourself moving and putting yourself in a good attack position.
Here's an edit I did of your replay where Instead of kicking off the ground and moving sideways, I moved towards uke. After that, it was really easy getting to uke. in your replay, you kicked off the ground with a contracted hip, which sorta just made you front flip to the side. I extended it back which pushed me forward instead.
The split kick and armthrow were just for show ;P
Also I dont suggest you learn walking until you are more used to your tori's joint functions and till you understand how to move around effectively. But if you really want to learn, I think there is a video tutorial somewhere that someone made. I cba to find it.