I see the note in the solver about needing to delete an command option if using astrometry version .68 or higher. When I load astrometry.net using the apt-get install command, it says it's loading version .67+dfsg-1

The astrometry page has a link to download the "latest" version. Should we stick with what gets loaded using the apt-get command or is it OK to install a newer version? Does Ekos care? And if downloading a newer version is OK, will extracting the .tar.gz file automatically put it in the right place for Ekos to see?

Probably the only reason to download the latest astrometry.net is IF you're using Remote Solver and IF you can care about parity being set. For most users, just use whatever comes with your distro.