ADE 3.0. Wont open

[lindas011940]

Hi, I was using Adobe Digital Editions to get my library books. But the recent book would not appear. It appeared in my computer but not in my Kobo. I was told I needed Edtion 3.0. So I downloaded that, but it says: The developer of this app needs to update it for it to work with this version of MacOs. 

[JaxB830]

I get this on Adobe Digital Editions version 2.0 and version 3.0. 

I have no access to my books and no help from Adobe... I feel like I've been robbed!