I have an old (25 years) oil painting where I blew the "fat over lean" rule and the dark paint "crawled" on top of the light paint under it. There are now light cracks showing in the dark paint. Two questions:
1) Can those cracks be filled somehow to lesson the effect? Due to the age of the painting, I'm assuming that the damage will get no worse.
2) Since the painting was never varnished, how should it be cleaned now prior to varnishing? There's no obvious dirt/smoke build-up and it was stored in a dark closet for many years.
Any suggestions would be greatly appreciated.
Thanks!

No one has written any answers to this question so if anyone is interested in what I've learned since I last wrote...

I've talked to a lot of painters about this problem and someone who did restoration suggested glazing over the light cracks with a dark glaze, letting the painting dry again thoroughly and then varnishing. (The painting did not crack through the ground, just the top layer of paint.)

Opinions on the technique, anyone? Feedback appreciated.

Janet