I am not a very big fan of the bar swapping. It just makes a real mess of my action bars(I like to keep things organized and where I can find things easily.) and its distracting as all giving hell with the action bars moving around like it does. 
I am not a macro guru and dont ever claim to be one. I just used an existing macro I have used for quite a long time during mists and expanded from that…
Anyway, This is what I came up with. (Took about 10mins.)
Use this for button 1:
/castsequence reset=target Curse of the Elements,null
/castsequence reset=target Immolate,Incinerate,Incinerate,Incinerate,Incinerate,Incinerate
/cast [combat] Dark Soul: Instability
Put Conflagulate on button 2 and use it every time when its not on CD.
Put Shadowbolt on button 3 and use it when you have enough embers to do so.
Put Shadowburn on button 4 when boss is under 20%
I wont know how this is gonna do until I raid Mythic tonight? But I tested it on a training dummy and was doing alright DPS to give this a try tonight. 
Let me know how it if works for the rest of you…
So I guess this will have to do until macros get fixed… ( * sigh * )
Tested out the macro. Seems to work pretty well. I was 1 or 2 in dps for pretty much the entire night.
Agreed, had to scrap Macro Toolkit as it is not working in this patch. I think I have a working Destro 1-button macro, at least it seems to work for me, and is under the 255-character limit for normal macros.
Here it is:
/use [mod:ctrl]Dark Soul: Instability
/castsequence [mod:ctrl]Chaos Bolt
/castsequence reset=target Immolate,Incinerate,Incinerate,Incinerate,Incinerate,Incinerate,Incinerate,Incinerate
/cast Conflagrate
The nice thing about this macro, is that once I have at least 2-3 embers and if any of my trinkets procs, I would hold down the CTRL button while mashing the 1-button macro and casts Dark Soul: Instability along with Chaos Bolt, it seems to work well for me. It also casts Conflagrate when it is available. Also note, I have 7xIncinerate because that’s the amount of Incinerates I need just before Immolate drops off. You may have to play around with the number of Incinerates as it is dependent on your Haste.
Give it a whirl and let me know your results.
Well since Macrotoolkit isn’t updated yet , I tested SuperDuperMacro and it works!!
superdupermacro cant work, the problem is u dont have the icon to put in bar, and they only cast cobra shot arcane shot and mend pet ability.
hey guys this is mainly for joe …I have a question for you …your stating that macro toolkit doesn’t work at this time in this patch did you happen to do the load all out of date addon’s only reason why I ask is that’s what I did and macro toolkit is working for me on my dk ok just tried it again it’s not working now on making them but it is letting me use the one that I had made for my dk…just wont save any changes sorry for the bad input on my part guys