According to the docs, the .dmg installers should be installers, but there is no installer anymore, instead at least for the last version I own, which is 9.0.97, Data Abstract for cocoa, the dmg opens up with just the app binaries and some folders inside the dmg, which you can drag onto your hard disk.
I think that means this page is out of date:
I suspect that the next step would be to open the frameworks and rebuild them with the latest XCode you are targeting, and to set up the frameworks so that they can be found from your other projects, or from one of the demo projects. I apologize because that’s a basic XCode task that someone familiar with XCode and its frameworks and its library path systems might find trivial, but the installer used to take care of that, back when Mac OS X frameworks like this product used to install in the the /Developer folder of your mac os disk.
It’s been a few years and a few mac OS x versions and what I’ve observed is that apple moved all that crap out of the root of the disk and there must be a new standard and new best practices.
What is the quickest way to get past this error when building an existing iOS app on XCode 11 or 12:
If these fail with errors like “not found” then the library paths need to be configured for XCode before an import like this can succeed:
/Users/xxxxx/mycontroller.h:19:9: ‘DataAbstract/DataAbstract.h’ file not found
Reading other posts here it seems XCode 12 now requires a new framework format?
And it seems that XCode 11+ requires ARC ready Objective C and that RO 9 was not ARC ready. I do not even remember if my own app is arc ready, so this is gonna be a fun upgrade.