Thanks for the guide, currently working my way through it now.
I just went through the backup stage using the google translated page. The comments regarding how it can brick your device are more to do with the usual risks involved with flashing, rather than the process itself. Rupor comments about this in subsequent replies in the thread.
As far as I can tell, the restore image just allows your computer to have access to all partitions on the internal memory via recovery commands. This means it most likely does not flash anything. (Please correct me if I'm wrong)
The main thing to keep in mind:
Ignore all prompts to format partitions. YOU CAN BRICK YOUR DEVICE
As tested on Win7 Pro 64bit. I suspect there wouldn't be any prompts to format partitions in Linux due to native support for ext2/3 partitions.
The process boils down to:
1. Extract rupor-rescue.7z to SD root. (gserial.inf is not required, and can be removed)
SD:\OS Firmware\files\update.img will be created.
2. Turn off PRS-T1 unit
3. Plug unit back into computer.
Cancel all prompts to format partitions
4. Boot into Recovery Mode (Hold Home+Menu until black bar if fully loaded)
Cancel all prompts to format partitions
5. Using Roadkill's DiskImage, backup the Internal Memory (1.82GB). Be sure to select the "Store Image" tab, and select where you want to save the .img.
Let it run (5-10mins) and you'll have the backup. Unmount, remove sd, remove the "OS Firmware" folder from your sd card. This is required before any attempt to root. Reboot and test to make sure everything is working.
gserial.inf is used for access via terminal, and it's usage is covered in the
original thread. I didn't use it to make my backup, and it wasn't even present on my sd-card at the time.
A note regarding the backup: it may contain your device details and other personal information, so it is best to store it securely.