I appreciate your response. However, I’m afraid it isn’t very helpful. There is no error code at all, just a blank screen when we attempt to access the dashboard. And we have used FTP and html/css/php editors to edit the files (neither of us are new to this). We have successfully removed and added back in all the customizations separately, and each one works without error. But the next time anyone tries to access the wp-admin area, we are not able to.
Anyone else have a suggestion as to what might be causing this? All code snippets used are Genesis/WP correct. No error messages, and code has been entered through an editor and was verified as we went.