Paint Shop Pro :: Flatten Layers Periodically While Working On Image

As a very long time user of Paint Shop (back to the early JASC days) and using the program primarily for producing bmp and jpg files with lots of graphics, an irritation in later versions has been the need to 'flatten' the layers periodically while working on an image. In past versions (don't remember how far past) one could set defaults such that you automatically worked in a single layer. I don't specifically remember how this was done (only that it could be done) and have not 'rediscovered' how to do it in my current X3 version and assume it will be the same in my (on order) X4. Is there a way to default into single layer work?

BTW: I strongly second the dislike of the graphite color scheme so certainly hope X4 gets 'fixed' to allow one to get rid of it.

I also note that after using the pop-up that appeared in X3 startup to order X4, my X3 became inoperable and had to reload it!