We've also ordered various DVD's through Amazon. Sometimes they come through okay, but some seem to be randomly stopped by the customs/censorship board. If that's the case you have to go down to an office in the Singtel tower nr Somerset where they'll open the box in front of you. In our case, although the DVD's were all freely available in Singapore, because they hadn't been censored they all had to be sent back. There is an option to have them viewed (you have to pay per hour) but if they find anything deemed unsuitable then the DVD has to be destroyed (as you can't edit a DVD). With videos etc they will cut them.
We just sent ours back to Amazon (you have to pay postage) and our money was refunded.