here is MSBT author feedback to the ui forum, it might interest you.
There seems to be a bug with GetSpellCooldown showing abilities with incorrect cooldowns due to runes.
This can be seen by using Blood Strike and then using it again 3 or 4 seconds later. After using it the second time, do /script print(GetSpellCooldown("Blood Strike")). The duration parameter will show 10 seconds even though not only does Blood Strike not have a cooldown, but even if you want to consider it on cooldown because of the runes, the first rune will be available in 6 (or 7) seconds therefore making the ability ready again in that time as opposed to the reported 10 seconds.
I personally don't think GetSpellCooldown should be reporting an ability on cooldown due to runes at all, but if it is then it should at least be reporting an accurate value.
well it's pretty easy to test at 61 just switch forth and back btw frost and blood presence, and when those rune are down you'll se the frost/blood presence icon appears as a cooldown. This of course is a Rune cooldown and shouldn't appear :)
there is an easy way to do this, make it so cooldown below 10s do not appear for a DK since every rune cooldown is 10s or lower and the lowest CD ability in a DK book is Death and Decay at 15s. (or make this a slider timer option ala MSBT cooldown)
update: i forgot mind freeze is at 10s but since it doesn't use any rune... something of a mix solution ? :)
yeh doesn't work with DK cooldown, when a rune is on a cooldown it shows all the related abilities on a cooldown which is a lot.
i think there is no solution for this and cooldown can't be used for DK unless you find some function in the blizzard code that reports the real cooldown on a spell and not the rune cooldown but i believe these 2 get mixed so...
adding the rune as cooldown ? you mean ignoring the rune cooldown ?
mmmh the spell by spell filter seems better to me because maybe there is that one ability that you want to see when it refreshes even if it's every 10s.
a DK has 6 Runes, each rune has a base cooldown of 10s, there's 2 blood runes, 2 frost runes, 2 unholy runes, most DK abilities use Runes as "fuel" for example : i can use a blood rune for a blood strike two times and then i have to wait for my blood rune to refresh.
what happens with CDB is that for example if i use blood strike twice then all the blood rune abilities of my spellbook shows up as a cooldown button and since they are not listed in the Save and Hide spell lists i can't hide them.
the only abilities listed are those with a listed Cooldown, for example Vampiric Blood has a 1min CD, but the thing is it also has a Rune Cooldown which is the DK mechanic.
so how to fix ? easy as pie, just list all the DK spellbook in the Save and Hide spell list so i can Hide those abilities i'm not interested in, and i don't see any other way to do this because basically everything a DK use has a cooldown (the Rune mechanic). (altho you could implement an ADD button to the spell list, like for the item list, so i can type in the spell myself instead of fetching it from the spellbook, but that would be less elegant)
anyway a simple solution would be a filter in the Save or Hide pannel where i could hide the specified cooldown, because at the moment the only spell listed are the one with an Ability Cooldown, but since every DK spell has a cooldown (due to rune mechanics) they should all be listed.
that would solve it for DK, and it's a very customisable solution so it's all the better.
ps: btw i have no idea what is the purpose of the Spelltree: Blood/Frost/Unholy in Save or Hide, i tried messing around with them but it doesn't do anything.