OK, let me summarize what I learned from this thread!
The front line support at LG did not know this, and I see a number of people had the problem of upgrading BD-530 firmware.
I figured it out and wanted to let folks know.
I connected a LG BD-530 Blu Ray to the Internet for the first time.
It was running BD.4.784.00.C
It tried to auto upgrade to BD.5.277.00.C over the internet.
It downloaded, but the upgrade failed. The upgrade hung as it started after it downloaded. I got stuck at the screen that said "Updating, Please wait, Auto Power Off"
I tried it every way (USB, Internet, Disc), and it would not work.
Finally, from a 3rd party site (provided at post 412 in the thread, thanks!) I got a copy of update BD5.227.00.C. I put it on USB and it worked.
After that I was able to upgrade to BD.5.277.00.C.
So - LG should probably put the 5.227 release on the website, or fix the 5.277 release so it can update the 4.784 release.
I called support at 800-243-0000 - they are sending me an update disc, but I don't know what will be on it.
4.784 to 5.277 update fails. (The auto update)
To update, the steps need to be
4.784 to 5.227 to 5.277.
Hope this can help someone.
AVSForum was a lot of help.
5.227 firmware package: http://www32.zippyshare.com/v/25854786/file.html
Found from the AVS forum thread (post 412) http://www.avsforum.com/t/1282080/lg-bd-530/390
If you like the REALLY old firmware, 4.874 is at http://www25.zippyshare.com/v/47426114/file.html