As promised, there is now a PND version which updates ANY previous OS version to the most recent one as well.
The only changes from HF5 RC2 were the updated splashscreen and a minor fix in the WiFi toggle script (it didn't end properly).
Here's a list of changes from HF4 on:
Download the full flash version here, or download the PND version here.
How to install it?
NOTE: This HotFix will REMOVE a few tools! Pidgin, Gnumeric, AbiWord, Clawsmail and the community backgrounds will be REMOVED to save NAND!
Those apps are already available as PNDs and work better than the NAND versions. I will release all the community backgrounds on the main website as well soon.
Simple: Copy it to your SD Card, run it and follow the instructions on the screen.
Takes about 7 - 10 minutes, so be patient.
Check for any error messages afterwards, but unless you haven't filled up your NAND with some stuff, it should all go smoothly.
You won't lose any of your settings.
2. Full-Flash Image
Note: When flashing a full-flash image, you lose ALL your settings. The unit will behave as it was just brand new.
Easy: Download the zipped image and extract the full contents onto the root of your SD Card.
Put the SD Card into slot 1 (the left one), switch on the Pandora while holding the R-Shoulder button and select "boot from SD1:1"
The flashing process should start. After it's finished, reboot the unit.
The first boot will take a while (up to 10 minutes). Patiently wait and you'll be greeted with the First Boot Wizard.