After the most recent update the UMD requirement for murderous intent (Scythe) seems to be off.
If my recollection is correct, previously murderous intent could be used once your UMD cleared a 10 (which made sense since you had to have at least a 10 to emulate the alignment gap). Currently, I cannot wield it even with a 20 UMD score which per the nwn wiki should clear a character up until an item value of 20,000 when emulating alignment, which would be a higher value than the cap of 8k on the new item proposal thread. So, something seems a bit off. I built the scythe in the toolset and before the deduction for evil only, its value floats around 6300.