email the affirmation to yourself, then when you go to the embassy and you need to make amendments then it won't take you no time at all, they have a computer you can use.
as for not recognising affirmations, I wouldn't worry about it too much, there are a lot of places you can use, we used
Chatuchak District Register Office (Amphur)
5 Soi Vibhavadi Rangsit 34
Chatuchak, Bangkok, 10900
They were great, and this was only last June