Trouble with step 3 of mysource matrix install

Hi Marcus, I tried this script https://matrix.squiz.net/manuals/server-administrator/chapters/backup-script

After having some issues with the dumpfile.dump file, I was able to complete the setup.

But when I tried to access the site, I got this ERROR …

Matrix Error
[ASSERT EXCEPTION] Asset “session_handler_default” is not installed on the system, unable to include its source file [SYS0320]

Then I saw this thread and ran the Step3 script again and I am back to square one …

Installing core .. ±--------------------------------------------+

Matrix Warning
Asset #12 does not exist [SYS0087]
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PHP Error
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Argument 1 passed to MySource::setCurrentUser() must be an instance of User, null given, called in [SYSTEM_ROOT]/install/install.inc on line 585 and defined
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