Magic Bow + Magic Arrow (effects question)

[codemephit]

I am inputting an NPC with a +1 composite longbow. she has normal arrows and also a few sleep arrows. I could use a little help figuring out the correct syntax to make this work correctly.

I know I could just manually hand-jam the correct values in, but I figure something similar to this might crop up in the future, and I would prefer to understand the correct way to do it vs. just glossing over it now. (i.e. if she lost her magic bow and picked up a regular bow for a while - the effects need to be properly entered for the sleep arrow to account for that)

NPC Window -> Main Tab -> Attack Field

+1 composite longbow +11 ranged (1d8+1 piercing/20/x3)

NPC Window -> Spells Tab -> Sleep Arrow Effect

Sleep Arrow; ATK: +1 enhancement, ranged

When I make an attack with a normal arrow, I just click the combat tracker entry for her longbow and she rolls 1d20+11. This is correct.
When I add the Sleep Arrow's effect, and click her longbow from the combat tracker, she rolls 1d20+12. This should still be only a +11, not the +12.
Both of these items have a +1 enhancement bonus and therefor should not stack.

It seems as though the +1 from the bow is not being registered as an 'enhancement' bonus, so it is allowing the two bonuses to stack.

Any help figuring out the correct way to enter these two items would be most appreciated.

-CodeMephit

[Trenloe]

It seems as though the +1 from the bow is not being registered as an 'enhancement' bonus, so it is allowing the two bonuses to stack.
NPC code doesn't get to this level of granularity. All FG sees is that it is a longbow (it will apply the piercing damage type based off matching the weapon name) and it sees that there is +11 to hit. As far as FG is concerned the +1 is just a label. You'll have to manually apply the sleep arrow effect only if the NPC doesn't use a magical bow to shoot it.

[Nylanfs]

Also note that they have errata'ed that magic bows and magic arrows don't stack. Which in my mind is slightly silly, just like Improved Crit and Keen don't stack.