Migrating between Lightroom CC, ACR?

I am interested in being able to start edits in Lightroom CC and move them into ACR to finish before opening in Photoshop. The reason is that I like to start with edits on my iPad and more easily make selective edits but use ACR on my desktop as it has my reference monitor and a user interface I am more familiar with. I want to know what are the best ways to transfer an in-process image,  if I can do so without needing a new DNG, and if anyone has found trouble with this. The challenge I have found is that an image that opens easily in Lightroom CC with many selective edits often won't open at all in ACR or, if it does, editing becomes sluggish. I'm wondering if that is due to the programs being optimized differently.