According to this post. "The next snapshot, and Minecraft 1.2, will automatically convert worlds to the new format." So with that in mind when using PMImporter to convert .mca to .mcr which in doing this removes all non PE blocks from the PC world. Now to allow me to open it into mcedit i need to be able to convert back to .mca. According to the post by mojang this should be done automatically when the worlds loaded back into MC this doesnt seem to happen but instead it generates a new world. Can anyone give me any advice or simply tell me where im going wrong? Thanks in advanced mightysun99.