Unibeast doesn't show OS

[AvaGardner83]

Hi, please forgive me if someone has already answered this question, but I can't figure it out!
I'm trying to create my USB stick with Unibeast and Mac OS Sierra. I downloaded the OS and it's in the applications folder, but when I go to create the USB it only shows High Sierra (which I don't have downloaded) and it's greyed out. Sierra doesn't show up at all (see screen shot). Any advice? Thank you in advance!

 

[Obvious Answer Man]

Are you using the version of UniBeast for Sierra?

 

[AvaGardner83]

Are you using the version of UniBeast for Sierra?

I was not, thank you

Maybe you can answer one more question? I get the attached error when I click continue to verify the installation options. Any ideas?