Hey Jeremy,
Sorry we didn't get around to you last night; you posted after we had gone home.
The first thing to try is a complete uninstall, so follow these steps:
* Uninstall the game the way you normally would.
* Open "My Computer" and navigate to C->Program Files->LDA Games.
* Delete the Rival Ball folder, if it's still there (the uninstaller may have gotten rid of it for you).
* Press the Start button on Windows and choose Run, then type "regedit" and press enter.
* A new window should pop up with a bunch of folder on the left pane. Navigate the folders to My Computer->HKEY_CURRENT_USER->Software->Longbow Digital Arts.
* If there's a subfolder named "Rival Ball", delete it.
Now there should be absolutely no trace of the game on your computer, so you can try reinstalling it again.
If that doesn't work, it might be something wrong with your computer. Here's a few things you can do to make sure your computer is nice and healthy:
* Press the Start button and choose Run, then type "sfc /scannow". This will run a "System File Check" on your computer to make sure none of the files on your computer got corrupted.
* Run a virus scan on your computer. AVG is a good (and free) virus scanner you can get at http://free.grisoft.com/.
* Run an adware scan on your computer. Ad-Aware is a good (and free) adware scanner you can get at http://www.lavasoftusa.com/software/adaware/.
If none of that helps there's some more information you can give us to help diagnose the problem you're experiencing:
* Is this happening in Rival Ball or Rival Ball Tournament?
* Does this happen in single player or online mode?
* When, precisely, does the crash occur? At any time during play, or just at certain key moments?
* What version of Windows do you have? (Windows XP Home? Windows 98?)
If you have any more problems don't hesitate to ask.