Yes. Here are instructions for how to define custom layer thickness settings.
Note that while this enables you to set the per-layer thickness, we don't yet offer variable layer thickness slicing. Therefore, you'll need to slice your model at thinnest layer thickness (highest resolution), as well as slice it at lower resolution, and then manually replace the low res areas with the high res areas, and renumber / recompile the image stack so that it adds up to the proper height.
Essentially, you'll have to experiment in order to get it to work. I'm sorry that we don't have a more clearly defined workflow yet. We're still working on this.
If you have questions or get stuck, I'll do my best to help you get this done.