I live in an old renovated country home, and the living room walls are 1x12 wood panels that have been coated very liberally with a thick wood varnish that has shiny lacquer finish. The color is dark brown, and makes my living room look smaller than it is. The panels also have small gaps in between most of them that would be too wide to fill in with caulk.

I'd like to paint over this, but I'm wondering how I can do this without making it look horrible and having it drip and not stick.

I would prefer to use a sprayer to get do the entire room. I like the wood panel look, and would rather not sheetrock over it.

I've seen primers that are made to use with these, but I'm a bit skeptical.

Is there anything I can do other than sanding, or has anyone encountered this before?