Ok, this is issue is really annoying. Got the latest version oh phpbbrc7 yesterday and have the same phpbb_admin_path issue where the acp module system is broken and trying to go to files one level too far back in the directory.
Seems to have something to do with the php realpath() function. Skipping the realpath function test in the functions file eliminates the problem on my machine...been fighting this for 2 hours now...
Existing:
Code: › if (!function_exists('realpath'))
Mod:
Code: › if (!function_exists('realpath') || true)