dashiichi: You can incrementally add patches if you go to Manage Installation | Configure from the game's Overview page; click the button on the far right with the two slider things).
You're far enough back that you'll need to download the new executable. If you have Galaxy installed, there's a link in the Extras tab.
Not sure how to get there without Galaxy, though.
I don't use Galaxy. Had to many issues and don't always have internet or good internet, so when I do, I usually just download the offline installable.
old1mike: Was wondering, Finally got to play this when 'fractal' came out. Have spent MANY hours exploring, building, etc.. Enjoy the open world (galaxy should say). Noticed 'interceptor' version out with MANY upgrades/changes. I am running 'fractal' ver 10088?. Don't have or see patch to upgrade from that, and rather than apply patches, can I just uninstall 'fractal' version and install 'interceptor' version and reload from saves from 'fractal'?
mbrowne: Instead of uninstalling, you could also DL and install 4.21 alongside your current version. Rename your DefaultUser directory to keep it, and you could run either one.
Will probably do this, but was wondering if I can use old saves from 'fractal', with all that I have collected/built etc.