I've found a UI problem in the bump-map plug-in dialog. If the open
files have to many layers, not all layers can be displayed in the
option menu. They fit not in a single column on the screen. To select
the layer you want to use for the bumpmap, you have to close all
unneeded files or to reduce the amount of layers.
Both methodes are not very suitable. Maybe we can replace the option
menu with a widget like the layer dialog.
I'm using Gimp 1.2.3/linux but think version 1.3.x has the same problem.
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