I've never touched Challenge mode in CSE, but I can help you with some things.
Your challenge 10 hurdle seems like a simple issue with Dive Cancelling, for all the details of DCing correctly, check the OP. The next Challenge 10 issue is range with connecting with j.c.
Try a super jump, or if that doesn't work, do j.a > j.b (1 or 2 hits) > j.c > j.d.
Trial 14 is yes, fast, the j.b link is pretty tight, but doable if you can't manage the j.a link because you're doing it too fast. Do it this way, don't worry, Challenge mode should register it as correct anyway.
6a > 5d > IAD j.a > j.4b