Using reflections on a bg with transparency

[AndyD]

Hi

I am having problems trying to produce an image with reflections. I have been doing it in the past with Xara4. My procedure is to take a number of images, create copies of them, flip them then add transparency once they are in place as refelctions. These are all placed onto a dark background; reflections are stretching beyond the background at this stage. And in the past if I select all, then Arrange>Combine Shapes>Intersect Shapes then I can have the whole image without the transparent regions of the reflections. My plan is to have the background transparent and save all as a png to preserve the transparency on web. But it doesn't seem to happen in my latest attempts. Instead at the Intersect Shapes stage I get a tiny part of the background as my final image.... I am confused, as you may be able to read, lol.
Anyone any ideas please...? Do I have to make a smaller image for the reflections rather than a copy/paste of the original images and converting to reflections by using the transparency tool?

I have set the background size to 960x235 but when saved and I check image size in the Open FIle window the image size is now 881x311....