At the moment I either use TFTP from uboot or mtd write directly to the firmware partition.
I would like to use the Luci system upgrade feature. However on the MAC1200R v2 this is not enabled. Where do I start looking to modify some system files that will allow me to use upgrade?
target/linux/yourdevice/base-files/lib/upgrade/platform.sh
And if needed for your platform:
target/linux/yourdevice/base-files/etc/uci-defaults/09_fix-checksum
Look over those directories from other models if they do not exist in yours already for hints.
Thanks. I looked at the platform.sh and couldn't find anything different then some other device I'm using (with working sysupgrade feature). Because of that I was thinking maybe I should look somewhere else too.
Turns out there is a discrepency between the platform.sh and the ramips.sh in the name convention. Looks like that is the same reason why I couldn't get the LEDs to work on my board 
I broke it with https://git.lede-project.org/d2b6bf141662429d542b23e9e8f44245a77710a5. I'll commit a fix later the day.
No, looks like you are about to fix it. It never worked until now. But yes, it's the little "-" that makes all the difference 
Well, it worked till I broke it. Anyway, I've committed a fix.