I took it apart this weekend, much gummed up oil that had turned to varnish everywhere. I had to pull the ejectors out, and remove the front wood to dismantle the triggers. I'm always concerned when fooling with Darne triggers, as the main spring comes out. The pin that retains the main spring has a small bend that is gunsmith applied at the Darne factory, and I don't have the magic to reset it, or fully understand how much is just right. I believe I have it reinstalled about how it was.
When the gun was built, a beautiful coat of lacquer was applied to the case colors, but, the trigger guard was missed-Monday morning gun? Friday afternoon gun? Too much wine at lunch gun? I don't know, but, I did lay some lacquer on the triggerguard to protect those lovely colors.
My lube of choice for Darnes I have apart is Breakfree CLP, with just a touch of Mobile 1 Universal synthetic grease on any screws I don't want stuck in the future, and, the rails on the breech block. Just a touch. I use the Mobile One on conventional hinge pin guns as well, cleaning it off after each use. The factory has always used Vaseline as a lube, good as it got when Regis Darne was alive, but, the synthetics should give better stability today. Everything is loosened up and ready for another 50 years or so of use.
I look forward to a little patterning work with it in the near future.

Best,
Ted