I created a new (hopefully stable) world in Mystcraft.
I then exited the game.
I deleted the region files and copied the region files from my old vanilla world over!
I now have access to my old world without heavy MCedit-ing!!
My old "standard" generators seem to be working, especially my Iron-golem farm
There are a few minor flaws with this-
There's probably more I haven't found out yet, but this does give me confidence I can start building bigger and better stuff. I can always port my current stuff over when redpower eventually gets released and I create my permanent world.
I then exited the game.
I deleted the region files and copied the region files from my old vanilla world over!
I now have access to my old world without heavy MCedit-ing!!
My old "standard" generators seem to be working, especially my Iron-golem farm

There are a few minor flaws with this-
I lost the inventory I was carrying (no big deal)
My minecart paths don't work as well (probably due to Railcraft changing stuff)
My enderchest inventory is empty (I'm not sure if that would conflict with the mod versions so probably for the best)
There's probably more I haven't found out yet, but this does give me confidence I can start building bigger and better stuff. I can always port my current stuff over when redpower eventually gets released and I create my permanent world.