sound to me like you didnt successfully save transparency in your tiff file.TIFF with alpha transparency - doesn't show up in the server at all - blank pane.
TIFF white-black w additional alpha - shows up as black.
TIFF white-black, straight - Comes up fine in server as white-black. Color effects applied to it (best: "invert mask 2") work to an extent.
there is a second tiff options dialog in photoshop cs when you save a tif.
it has an option 'save transparency'.
i just made a tif with 5 different vertical grads- some transparent some not.
if you load this into a catalyst layer - you will be able to see some of the blocks are transparent.