I can help on that. There are new macro conditions for bars.
[vehicleui]
When a player enters a vehicle that is actually a vehicle (like a motorcycle or a dragon)
[overridebar]
If the default UI switches to the overide bar but you are actually not in a vehicle (like the DMF games where you hold a hammer to slap gobilns)
Other new conditions are:
[petbattle]
To be able to hide stuff in the petbattle.
[extrabar]
To be able to tell when to show the extraButtonBar
[possessbar]
If you possess sth or someone you may get the possessbar. This will tell you when to show the possessbar. (This is just a two button bar with the possess spell and an VehicleExit() button)
Currently I got that all down in rActionBarStyler and you can check the state drivers that handle the conditions.
http://code.google.com/p/rothui/sour...nBarStyle/core
If you are not using the default bars ask Maul for help. He digged really into that when doing ION.
The problem lies within here, the new actionbuttoncontroller:
https://github.com/Ketho/wow-ui-sour...roller.lua#L93
Our macro conditions need to reflect all those conditions. Currently tempShapeShift is still missing.
If you are using the default bars you only need to know if the overridebar has to show up or not. Everything else will be loaded into the default actionbar anyway.
But what's really hard to do is when you need to do the actionPage swap of the bar by yourself.
You can ask specific questions on that in the MoP beta forums.
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