I do the oolite-update quite regularly:
Commander Getafix welcomes you to the Oolite Nightly rsync server!
Your installation will now be synchronized to the latest nightly build.
Your Oolite installation is already up to date.
Any missing or altered Oolite installation files have been restored.
I just went through my AddOns and I noticed I still have one outside the new in-game-AddOn-system:
I deactivated it and so far I had no crashes. I will leave it that way for a while, although I love firing with them while the lasers are overheated
Let's see whether this will solve the problem and then I will contact the maintainer of the railgun.oxp .
By the way: Does anybody know why it is not in the in-game-OXP-system so far?