I was here a few days ago with a similar problem, but I am now able to explain my predicament a bit better.
Basically, I got a few Alpha mapped planes that I need to fade in and out in the render. I don’t know how to do this, mainly because the alpha setting is already at 0.00. Any ideas? I could use the Sequence editor, and fade them like that, but I can’t get my Alpha mapped images to overlay on the video rendered background.
So either way I’m stuck, unless Im doing the alpha mapping wrong. I just turn on ZTransp. Put the alpha slider to 0, and check “Alpha” on the Map To section. ( I also UV Map the plan and get the texture on there with Alpha+Copy Draw Mode in face edit. )