Not sure if this is a bug, but I created a 468 x 80 banner background in Fireworks, and set that as the background for my costom screen. In the upload settings I selected “Make jpg”, and changed the size settings to 468 x 80, and selected the “Use” checkbox. I then OK’ed that, and saved the custom screen. It created the banner for me, but completely the wrong size (too small in both dimensions). In the end I have had to offset the size to about 494 x 114 which gives me a 469 x 80 image.
Also is there any way of changing the name of the output file, and uploading it to a different directory on the server?