Here is a new photo of Hoya praetorii along with a link to the third and final installment in my trilogy.  If this video and photo does not convince you to grow this species using semi-hydroponics, then I guess you are beyond convincing.  After only four months from taking the cutting, I have four open peduncles with a total of 53 individual blooms on the plant.  The link and photo:

http://www.youtube.com/watch?v=Al_W-eY3-sY&feature=youtu.be