[Therion] seperate layers for surface and sketch images

Hi again Getting back to the task of including our existing paper maps in our Therion datasets. We have a large cave, with the existing plans comprising more than 5 overlapping sheets, representing differing regions and levels of the cave. Is any progress planned on separating the sketches from the surface layer in pdf outputs? If so I'd like to put in a request for each sketch to have it's own unique layer, and to support the transparency feature already implemented for passages and the surface. Are there any issues related to this (other than large run durations and file sizes)? Bruce