Help with Saving my Projects?!

I just downloaded Scrivener and wanted to start my projects but I kept getting two error messages, one of which wouldn’t even let me start a document. I’ll post it as an attachment. Now for some reason, it’s letting me so I don’t know if the problem was resolved or not.

The other issue I’m having is saving my work. At first, it was sending me an error message (that I’m no longer receiving?) telling me that my work cannot be saved in any of the folders I wanted to put it in and is at risk for being lost. I couldn’t get a screenshot of that message. I just want to be sure that both issues won’t inflict on my writing before I get started.

Please advise!
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It looks like you are trying to save a project to the installation DMG. “Volumes/Scrivener” is the virtual disc you downloaded to install the software. I’d first make sure you’ve actually copied Scrivener to your /Applications folder, then eject that disc.