Rpgs have this problem. A base value is always expected to be in range 0:N, but modifiers are valid if < 0 or > N. Finally, final derived values are again expected to be within range of 0 to N when the dust settles. (This is not the case with statistical values but ZC doesn't have those.) I would assume that setting a counter (with implicit positive range) to -1 would set it to 0 and not 65535.
What are all the counters affected by this?
