The integrated eGroupWare-FUDforum package is currently abandoned and not maintained. Luckily the code is still available (see link below). Please let us know if you can help to analyse, document or simply the code so we can once again make it available to the community.
Installation instructions (please expand):
The following is a brief explanation of how the FUDforum installer (for EGW) works and what is necessary for it's correct operation.
Inside the fudforum/setup/ directory, which are you currently in, there is file called 'index.php'. When FUDforum is being installed this file will be copied from fudforum/setup/ to fudforum/[crc32 of your domain]/ directory where it will temporary assume the role of FUDforum's index page. When the forum is accessed for the 1st time this file will perform the necessary actions to complete the forum installation and upon successful completion redirect you to the forum's front page. The primary purpose of this file is to copy various forum files from fudforum/base/ into files/fudforum/[crc32 of your domain]/ directory. This is necessary to allow FUDforum to perform the necessary disk writes needed for normal operation. The file will also need to create several files inside the web browseable fudforum/ directory. This will require you to grant write permissions to the web-server to several files (installer will complain about them, if they are not writable) and directories. The simplest solution is to temporary chmod fudforum/ directory 777 and then restore to normal permissions once the installation process is complete.
If you wish to save a few megabytes of space, once the forum is installed you can remove the fudforum/base/ directory, it is no longer needed.
By default FUDforum will disallow anonymous user access, if you wish to enable it, create an anonymous user in eGroupWare and then in FUDforum's admin control panel enter that user's Login & Password into Anonymous Username & Anonymous Password fields. Once that is done, anonymous users will be able to access the forum. To control the abilities of anonymous users, use the FUDforum permissions system. By default anonymous users will only be able to view & search the forums.