I wonder what this button does: CiviCRM permissions
One more thing that gives people a hard time with CiviCRM permissions:
The meaning of each one is not always plain to see.
What's the difference between “access CiviCRM backend and API” and “access AJAX API”?
What about “administer CiviCRM” vs. “all CiviCRM permissions and ACLs”?
CiviCRM documentation used to provide some additional information on these permissions. That documentation is a little outdated, though.
The current documentation doesn't contain all that detail, because the permissions interface itself now contains descriptions for each one. And that helps a little.
But still, it's not always obvious.
When you’re not sure, and you don’t have someone handy to ask, the simplest solution is this:
Change one thing at a time, and test.
Document your changes. This is an extra 5 minutes of your time, but it will save your sanity two months from now.
Here's the thing:
Some parts of CiviCRM are more complex than others. Just like anything else, it can feel daunting the first time, or the first 10 times.
But the feeling of mastering your systems, and owning the outcome, is almost always worth the effort.
All the best,
A.