I often use setups from other, better trickers and try to add whatever move i want after them (Chilledon's scoots, DahStevy's raizes, etc) If I try to edit the replay anywhere before the set (jump), I jump into the ground or can't spin hard enough for corks. Any advice?

I can't view replays atm but here is something that can help you: http://forum.toribash.com/showthread.php?t=599223.
Its basicly corking tutorial so yeah.
And dont use other people's openers, or atleast stop doing that whenulearn making ur own

First of all, I'm gonna be saying this, never, never use other openers from better trickers or worse. Always make your own, you can apply to clans saying, oh, i made this but the opener was someone else's, thats not gonna help you out, you should always make yours.

You're asking for advices to land better corks, but you dont make your own openers, your openers are the key to the power of your tricks, you need to make good openers yourself, you're kinda being lazy and you can't be like that.

Here I am again, repeating myself over and over, make your own, practice your openers, when I'm making tricking replays too, i struggle to make openers, but, you can't just nab openers here and there and expect to get better.

First replay
It's good, there are some things you can practice to make it even better, don't extend your kicking leg's glute fully and don't contract the leg itself to the max, remember to contract the abs while in the air, and remember, a cork isn't a cork without a landing.
Second replay
A missleg is just a missleg, it isnt a missleg butterfly kick thing, and you dont do it like that, you transfer the momentum.
Third replay
That wasn't a hypercork, that was a normal cork landed with the kicking leg.
Forth replay
It's OK, but, you should kick your leg out when your 90º about to land, kicking it early made you lose spin.
Fifth replay
That wasn't a completed cork and I say again, cork isnt a cork without it's landing, contract your abs.
Sixth replay
That was another incomplete cork, dont twist your chest the other way around, twist it when you're 90º away from landing and when it reaches the middle spot where it originally was hold it.
Done cnc'ing
I'm gonna tell you another thing, don't make simple replays like that, you dont show much skill by doing that. Make long replays with a long combo of tricks. Only make small tricking replays if you're like Jagger or something that lands craaaazy stuff.

OK. Don't steal openers, and make longer replays.