I don't know about painting cedar. I have another suggestion for you to consider. We have a room that is paneled dark. At work, there is a room that is paneled with wood divided with white fabric panels. I asked my wife to consider attaching wide, white fabric "stripes" to the walls at intervals that would be attractive. It would brighten up the room and break up the monolithic panel look. We have not though about any detail yet. The fabric tone/color, attachment fabric type, etc are not even being considered yet.

I think fabric walls can be pretty. But, that's not what I'm trying to accomplish. This cabin, previously, had leaked. We are just finishing the re-roof and removing sheathing, insulation and spraying for mold. Their appears to be some mold on the interior surface of the cedar - maybe even painting under a layer of shellac the previous owner put down. ugh. Now that we've got one side of the mold addressed, we are ozoning the interior space. I'd like to seal/paint one room and see how it goes. If it looks OK, we'll do the rest of the cabin.