Since d2 tends to truncate values, will having +1 cold damage on a weapon trigger mdr?

1 damage *.18 pvp penalty *.25 resist penalty [truncated]= 0 damage
If damage is reduced to zero before mdr takes effect, would mdr overflow and continue to reduce physical damage or not trigger at all since there is nothing to reduce?

How would I test this?

1 damage = 1 hp = 256 bits

256 * 0.17 (pvp) * 0.25 (res) = 10.88

truncated in the process, probably twice (I can't say for sure) to 10.

10 bit trigger MDR, yes. Overflow applies to physical damage.