Hey Cass
Thanks for the heads up about Singapore Airlines. I've just booked with them, so it's great to know that I will have up to 40 Kg allowance due to my 176 visa ... happy days!
Re the paperwork for your 176 visa, I applied for mine through an agent and as part of the application process I had to send off my passport to them. When it came back it was stuck on one of the pages. Sorry to ask the obvious, but if you've had to do the same, have you checked your passport? Also, if you went through an agent it may be worthwhile going back to them to ask them about it.