My experience with PP renewal from Nepali Embassy in DC was pleasant overall. My communication with the Embassy was entirely through email (except once when I made a phone call), and it was nice. I got quick response from them whenever I emailed them. Here's what I did for PP renewal:

1. I bought A4 size paper from amazon and printed several copies of the application (filled) although they ask for two copies. I did that because the box for "lyapche" is too small and if you are not careful it will be touch the margin (and they might make you refill the application).

2. I did not send the original Citizenship certificate, but just the copy. Although they say it will take longer, but I received my passport in exactly 10 weeks from the day I sent the application for renewal.

3. I took the picture at home, printed at walmart (2" x 2") and sent them in a ziplock bag. I let it to them to cut the pictures to the size they require.

4. For money order they say that it should be valid for at least one year. The money order I sent was valid for only 90 days and I didn't have any problem.

5. I went to FedEx and they opened an account for me. I printed the return slip put it with all the documents and sent in FedEx reusable envelop so that I don't have to send an extra envelop.