I had to change any reference to HTTPS_CATALOG_SERVER to HTTPS_SERVER since that was how my default config.php file was set up.
My /phpbb2/config.php file looked nothing like what the instructions showed, but that may be because the instructions do not show the actual db name, password, server, etc. I just copied the top section from the replacement (from the if statement to the last require statement) in the instructions and pasted it in the top of my phpbb config file, and it worked for me.
My SQL statement in /phpbb2/login.php was longer than the one that the instructions showed, so I only replaced part of it.
The instructions use .php as the extension for some of the tpl files, but I figured that out.
The instructions for /phpbb2/profile.php assume that the server is HTTPS, but mine isn't so I had to change from HTTPS to HTTP in some of the new code.
That's about it.
I did a temp fix to get around the errors on login.php - I didn't paste in the new code, just left catalog/login.php as was. :-"
I did some testing after I installed, and when I logged in as myself in the catalog, a new user in phpbb was created. :thumbsup:
But I was not able to log in to phpbb after that, even as the admin. :blink:
It kept giving me an error - I forget what it was. This may be due to me not putting the code into catalog/login.php, or some other bug I introduced by making changes to your code.
HTH