Bongo, Flamingo nxt and Rhino basic materials. Please help


I am looking to do fade in/out of objects by changing the transparency of materials, however I am also using Flamingo nxt to render so have come across the inevitable problem… please see the links below.

I have tried doing the fade in/out with a basic material which DOES work in Flmaingo nxt, however, whenever I start editing the material I get stuck. Is this simply because it is no longer a basic material once edited? I am trying to add .TIF files to the colour, transparency and bitmap of the material. Each addition gives me a more curious development of how it is not working.

To sum up, should I give fading in/out a miss when using Flamingo nxt to render? Or has anyone had any success in doing this?

Thank you,