Instead of adding an Application of Donation to your payment, you can choose Other and specify an other Type.
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To add new Other Types, follow these steps: 
  1. Go to Administration > Code Tables 
  2. Find the Revenue Other Type Code Table. This will appear in the Revenue Category. Click the hyperlinked name of the code table. 
  3. Click Add to add a new entry. 
  4. You can now use this as an Other Type on a payment. You will still need to specify a designation on this payment.