That is a great idea pbacot thanks will report back when I've tried it!
EDIT: Ah, it appears that colour to alpha is for Gimp only not PS, in PS you have to use channels apparently. I'll try it in Gimp, at least I know now that I have to make the image transparent before I import it into SU!

Hi all, even though I used SketchUp 8 a few years back I hadn't used it since until recently as we've finally got a new PC with a decent graphics card powerful enough to make it a joy to use.

I'm still a noob at this although I've made three models. I've just finished a model of a house I'd like to build in Spain (haha fat chance.) There's a flythrough here on YouTube where you can see I've used stained glass windows I've downloaded from the 3D Warehouse. But what I want to do is make my own stained glass window which will cut openings from a png saved from PS.

I know how to make components which can cut openings and I can import a png with transparent background of a stained glass window I've cut out in PS, but what I can't figure out (and I've googled the hell out of the question) is how to make a transparent stained glass window cutting component like this one in the 3D warehouse. How do I make the actual stained glass transparent? I've read something about painting each individual colour with transparency but there has to be a simpler way!

All help gratefully received.