custom payment amount

Thank you for putting this plugin together! I’ve been looking for something just like this. Quick question.

I need customers to be able to enter custom payment amounts. The only way to enable custom amounts in the plugin is to set it on “Donation” mode.

Does this change the way Square processes/categorizes the money? As far as Square is concerned, would it be OK to set the plugin on “Donation” mode to accept business payments? I just don’t want to cause any tax problems later because something was marked as a donation.
Thank you!