Polymorph AC and stoneskin

[Nylo]

While polymorphed into an ape, I'm noticing what seems to be a bug. Using buffs dragonskin, armor, shield, stone skin, acidshield. With an AC of around 28 in ape form, depending on buffs, my stoneskin is getting hit basically every attack. But it doesn't seem like the mobs are actually hitting most of those times, because the acidshield only triggers once in a while, about every ten or fifteen hits. When I'm fighting the same mobs unpolymorphed, with similar or less AC, they hit me only occasionally, about as often as I was seeing acidshield trigger in ape form. And acidshield triggers every time.

I'm not sure I explained this all real clearly, but to summarize - when polymorphed, my stone skin seems to be taking full damage even when they miss me.

[Raona]

I don't see a difference between when polymorph is in effect and when it is not, but there IS something amiss when stone skin is in effect and the attacker is using a weapon with an elemental damage apply. When you are hit, you get hit twice, with two echoes and double damage to your stone skin. When this happens, it looks like this is logged:
BUG: Dam_message: bad dt 150
I'm guessing that means there is code in place to try to deal with this situation, but something about it is not quite right.

Sidenote: When stone skin prevents you from taking any damage, you get a somewhat misleading echo saying you sidestep or duck under the attack, the same echo you would get if they had actually missed.

To reproduce: Put two testchar PCs in killmode spar, one with stone skin, the other with a weapon with an elemental damage apply (like i110218). Attack, then begin spamming MSTAT on the PC with stoneskin. If there is a hit, two "X's stone skin absorbs some of your damage." echoes will be seen in immediate succession (well, with one of those misleading miss echoes inbetween) and the hitpoint count for the stoneskin (seen in the spammed MSTATs) will be reduced by 2x the amount shown as the damage from the hit. For example:

Spell: 'stone skin' modifies affect by 151 for 5549 rounds with bits stoneskin.(Gorby,18)

Your roll was 14 (-2) AC was: 12 dodge:0, parry:0, shield:0 Sur:0(M:0 CS:1 FF:0), Fla:0
Total damage: 3, Weapon damage dice is: 1d8+0 (dam bonus: 1)
Transmutar's stone skin absorbs some of your damage.
Transmutar ducks under your slashing attack.(0)
Transmutar's stone skin absorbs some of your damage.
Log: [*****] BUG: Dam_message: bad dt 150.
Transmutar sidesteps your attack.(0)

Spell: 'stone skin' modifies affect by 145 for 5549 rounds with bits stoneskin.(Gorby,18)

This is part of the reason for elemental damage applies being turned off at present. Was your assailant in this situation attacking with something that did elemental damage?