upgrade from 2.2.3, move server, admin hack questions

[MRs2]

Hi, I have a few questions:

I just became admin of a club forum that still uses 2.2.3
I advised the club to upgrade, and they are willing to do so. I am new to vB, PHP, MySQL, although I start to grasp it now.

• Upgrade to last version has to be in two steps. Are all (older) scripts still available?
  
• I just became admin. But I have a few problems that need to be solved before upgrade:
  1. in the admin cp I have most rights, but not all. When trying to edit a custom template I get an error when I want to save it (You don't have permission to access to this document on this server). I can edit it directly in the database though. All files in the admin directory have the same protections, so I don't see why I can acces some, but not all. The same with moving a user to another status (also possible in the database)
  2. When someone registers as new user an auto message is sent, using two custom templates (for header and message). But this still comes from the pm-box of he previous admin. I can't find where this comes from. I changed my user.pmpopup to 2, and his to 0. I have no settinggroup.title "default pm" or something like that.

By now I must have read all PHP-files in the admin directory, read all tables in the database, and went through a good bit of your forum.
Some help would be appreciated, for I want to be sure that I will not bump into either permissions, settings or missing scripts when upgrading.


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update: I found the answer to one of my questions finally.
auto-message sent to new users now comes from my userid:banana:

The other two are still open