Please PM (see my signature for link) backend super administrator login credentials and will take a look.

CB was out of date. You had latest stable, but we've had several build releases since then and have updated your install for you.

As for what's causing your issue. You've a Redirect and Auto Login auto action on the onAfterUserRegistration trigger. That trigger fires before activateUser function can activate the user. In the activateUser function is a trigger that CB Auto Welcome acts on. This means you're redirecting before CB Auto Welcome has a chance to do anything. I've corrected the trigger for both to onAfterSaveUserRegistration which is fired after the entire registration process is fully complete. The redirect action was also redundant so has been unpublished. I've confirmed CB Auto Welcome works fine now.

Please also note you've several tabs incorrectly setup for the canvas layout. When placing tabs in "Canvas Main Middle" tab position their display mode needs to be "Tab Menu" or "Nested Tab Menu" or they won't display correctly or at all. I've corrected all the incorrectly configured tabs for you. If you do not want to use the tab menu display mode you will need to use a different tab position as that position is not designed for any other display mode.

In addition to the above the usergroups assigned to your admin user do not appear correct. No one should be assigned the Public usergroup directly. Your user typically should only ever have the Super Users usergroup for global permissions to access everything. So you may want to also correct that or you could now or in the future have permission problems.