Well technically you can, but depending on how you set-up the game, it can be hard or easy. There are patch scripts out there though I haven't tried any of those, but mostly, you need to determine already at the start if you wanna make patches or not.
As for me, I'm just updating files that need to be updated and adding files that needs to be added. no scripts or whatever.
Thanks for the interest in this, I hope you do find it fun. If you do, tell your friends about it too, that will help a lot.
@Makio - check out the VIP area
EDIT: Added a game manual, check it out on the first page