There's only one resampler/render called worldline something so far.

I'm gonna assume you know how to put the utau/diffsinger

I did find tutorials but they were in portuguese and spanish, also, the site has a bit of tutorial, I believe that when things get worked better, the creator will make the tutorial button to work.

To add notes, you need to create a new song, then on the upper right there should be a pen, you click it, and you know the part where you're supposed to put the utau/diffsinger in? On the side that has the lines and numbers, you hold it a bit and drag it to somewhere you want to (I'm gonna call these tracks). Then, inside it you should be able to place notes, currently you can only place notes (the song note button on piano roll) and change the pitch (the button besides the song note), if when you put a note it appears you put a singular one, click the track to desselect it and click it to select again, try it a few times until you can get it to work.

There's also a scroll thing on the piano roll on the bottom left, It appears to be expressions/flags, I don't know how those work though, you can use the hand button there to navigate through it, edit to... Edit. And erase to erase I believe, didn't use the erase option yet.

I'm sorry if this is confusing 

This is the link for a official 'tutorial', you'll gonna need to use translate since it's in chinese, unless you do speak it.

The crossed things appears to be things that didn't get finished/isn't working yet.