If they just run "ctest" right after the installation (which is a very good idea), I assume the SAXS tests will run by default, and they will get a lot of failures and be confused. Of course if they can be easily fixed that's also a good solution :) But otherwise, it is nice if after you download the release and run cmake, you will get a completely clean result, assuming that all went well with the installation.
perhaps remove those SAXS failed tests from the release branch? It is
nice if users get a fail free release (so they can know if they have
real installation problems)
I don't see what that buys you - the non-working code is still there. If someone manages to get as far as running the tests while still having "real installation problems" most likely all of them will fail anyway - that should be obvious.