Setting a car loan

[Andy Pastuszak]

I tried to set up my car loan in Gnucash and the calculated monthly payment
doesn't match what the bank says I owe.  Gnucash says the monthly payment
should be $294.78, but the bank makes me pay $299.11.

Thing is, I put the loan into other financial software and also comes up
with $294.78.  So, it's obviously not the math that Gnucash is doing to
calculate the payments.

Is there some way to deal with this situation?  Am I just stuck entering
transactions manually?

The loan has 61 payments, and I am thinking that payment 61 is probably not
a full payment and that's screwing up the math.

Is there a way to deal with loans that have a final payment that is
different from all the others when trying to schedule payments?