As mentioned before, they may require a higher downpayment. When we applied, I asked about this. I have very good credit, but my co-borrower had a bankruptcy five years ago (but had actually rebuilt his credit quite nicely since then). Our guide said that our application would either be accepted or rejected, if rejected it would most likely come back with a request to put more money down. We were going to do 20% down anyway and had no problems.
I have read postings by others on here, where they were told that they needed to put more down. I believe that one poster indicated that they had to put 30% down, most of the others were 20% to 25% depending on the situation.
The loan is secured by your points. Disney is well protected. If you default, Disney will take the points back and sell them to someone else. Because of this, they can take on riskier loans.