Hi Micah!
Now I think I understand what is happening - it looks like code was pasted into your business' email address field at some point on the settings page. I will upload a new version to check for this condition sometime this week, but in the meantime, if you edit dgx-donate-paypalstd.php, and look for this line
$payPalEmail = get_option('dgx_donate_paypal_email');
keep that line, and add these lines after it to clear any bad setting in that field
if ( ! is_email( $payPalEmail ) ) {
$payPalEmail = "";
}
Let me know if that solves the problem and lets you enter your PayPal email address. Then your donation form should work.
Cheers,
...Allen