I've had the notes kicking around for absolutely ages. I haven't checked to see if this stuff is still accurate because during the last 12 months or so our viewing habbits have changed and we almost exclusively watch streamed content now.
That said, my father-in-law gave us a Humax Foxsat HDR Freesat digital recorder as a thank you for some work I did for him. It turns out the Humax Foxsat HDR is quite hackable.
Hard Disk Upgrade
I contributed to the topic below. The Humax firmware only supports disks up to 1TB but the hackers method works for 2TB drives, possibly bigger but I haven't tried. I've upgraded mine and my father-in-laws to 2TB without any problems.
These are the topics that discuss the custom firmware itself and includes the downloads. Once the custom firmware is installed and it's advanced interface has been enabled you can enable several add-ons such as Samba, Mediatomb, ssh, ftp, etc.
This is the topic about the web interface. No download required it is bundled in the custom firmware above.
The channel editor is installed and configured via the web interface and is one of my favourite add-ons. It also allows you to enable non-freesat channels in the normal guide.
Non Freesat channels
We get our broadcasts from Astra 2A / Astra 2B / Astra 2D / Eurobird 1 (28.2°E). Other free to air channels are available and KingOfSat lists them all. These channels can only be added via the Humax setup menus, but can then be presented in the normal EPG using the Channel Editor above.
Decrypt HD recordings
I never actually tried this, but what follows might be useful.
This is not so relevant now, since Humax haven't released an OTA update for some time.
I have not yet found a way to prevent automatic over the air updates from being automatically applied. When an over the air update is applied the Humax still works, but the web interface and all the add-ons stop working. The can be solved by waiting for the custom firmware to be updated (which happen remarkably quickly) and then re-flashing the custom firmware. All the add-ons should start working again.