Rival Ball normally detects installed DX-Ball 2 board packs through a list of predefined directories, so if the path to your DX-Ball 2 installation is not listed, the purchased boards will not show up in the game.
Unfortunately, it seems the current installer for Rival Ball 1.5.6 does not list the default directory for DX-Ball 2 version 1.3, which should be at C:\Program Files (x86)\Longbow Games\DX-Ball 2. However, you can still add it manually by editing the directory listing file 'dirs.cfg', which is found in the Rival Ball directory. To access this file, you can follow these steps:
1. Right-click on the shortcut for Rival Ball and choose 'Properties'.
2. Click the 'Open File Location' button, which will launch the Rival Ball directory.
3. Right-click the file 'dirs.cfg', select 'Open With' and launch the file in Notepad.
4. Access your DX-Ball 2 directory by repeating step 1 and 2 with the DX-Ball 2 shortcut.
5. Click in the address bar of the DX-Ball 2 directory and copy the selected path.
6. Now, paste the path (e.g. C:\Program Files (x86)\Longbow Games\DX-Ball 2\Boards\) and save the file. Remember to include the backslash '\' at the end of the path, or Rival Ball will not detect the directory.
If the path you added is the same as the directory of your DX-Ball 2 board packs, the boards should be available next time you launch Rival Ball.
Note: if Windows will not let you to save the changes you made to the 'dirs.cfg' file, you will have to exit the file and change its permissions first. To do this, you can follow these steps:
1. Right-click on 'dirs.cfg' and choose 'Properties'.
2. Switch to the 'Security' tab and click the 'Edit' button.
3. Select 'Users' in the list of group and user names.
4. In the list of permissions below, check the box 'Full control'.
5. Click 'Apply' and close the properties box.
Alternatively, you can make a copy of the 'dirs.cfg' file on your desktop, add the missing path, save the changes, and then replace the original file in the Rival Ball directory. In this case, you should be prompted about whether to complete the action, as opposed to being restricted.