Here's a very minor glitch with payment to Paypal personal accounts.
A customer placed an order but didn't pay right away (which is possible when paying to a Paypal personal account). Instead, he sent a message to remove a few parts from the order. I did as asked by "More Actions" -> "Refund" and removed the parts.
The Paypal payment link provided on the order's page still asked to pay the full amount, without any deduction for the removed parts. The customer might have been a little confused but he paid the full amount, and I then refunded the difference.
Also, the order's status wasn't automatically updated when the payment was sent, but I suspect this is already known when a payment is delayed.
P.S. I know Paypal personal accounts are inadvisable, I'll switch eventually.