First download 0.5-rc2 through the torrents.
Make a backup of your old configuration files (best just rename the directory) and allow the new client to start with a fresh configuration.
The configuration files are in the "~/.PlaneShift" directory on linux, "%AppData%\PlaneShift" on windows and "~/Library/Application Support/PlaneShift" for a Mac. Just rename that folder to something else before starting the new client.
Then execute "pslaunch" with the "--repair" options. For linux just open a shell (konsole/terminal) and go to the directory you installed PS in with "cd <directory of PS install>". There just type "./pslaunch --repair".
For windows open "cmd" (command prompt) with the "run" command from the menu or hit <windows>+<r> and type "cmd". Then you have a command prompt. Go to the PS install directory with "cd <directory of PS install>" (for example "cd C:\Games\PlaneShift") and type "pslaunch --repair". With the shell/command prompt you can see the progress of the updater...it really takes ages, about 2 hours for me.
After updating start pslaunch, do some settings (for example I needed to change the sound renderer to software again to get decent sound). Then you can try to start the game.
If you get in the game, logout again and copy the content of you "logs" directory of the backuped old configuration to the new one to get your old chat logs, the "options/shortcutcommands.xml" file, the "options/controls.xml" file and if you changed the chat filter the "options/chat.xml" file to the new configuration. This should give you all shortcuts, keyboard settings and a changed chat filter back.
Edit: Sorry about Mac users...it works about the same, but I have no idea how to open a shell/console on a Mac.
