A negative category is created to deduct points from an existing score
with each question answered. The problem here is that when you select
a template with only a negative category there are no points from which
to deduct from. The template has no value in points. This has been
identified as a bug in AMETHYST and will be addressed in a later version.
Please subscribe to our mailist so you may receive notification when this
has been fixed.
Alternatively, a way to temporarily avoid this is to first create a
positive category within a template and then create a negative category in
the same template.