The enclosing folder is of course htdocs, in MAMP. htdocs already had Read & Write for admin. So I then 'applied to enclosed items (cannot be undone).'
Unfortunately, the same permissions error, as in the screen shots above, continues to block the wizard.
Of more immediate concern however: I am concerned whether I may have opened up an exposure, by putting admin Read & Write on all folders and files in all my sites in htdocs. Can you advise?
I can 'restore' from Time Machine. But of course I need to do that as quickly as possible, since I cannot work on MAMP files in those sites, until such a restore is completed.
Then we can address the ongoing unhappiness in the install wizard
Thanks for the help, David