Now you understand the importance of Nandroid backups.
You don't need to use an SD card adapter - the Amon_RA recovery boot has a menu item called "USB-MS toggle" - which will allow you to manipulate the SD card from the PC over the USB cable.
Just be sure to observe the following protocol:
1) Boot into Amon_RA
2) Plug the phone into the USB cable to the PC
3) Wait a little bit, and then choose the "USB-MS toggle" menu item in Amon_RA
The SD card should appear on your PC as E:, F:, G: (or similar)
4) Manipulate the E: (F:, G:, whatever) drive as you see fit
4.5) Wait a few minutes.
5)
Be absolutely sure to use the "Safely Eject Hardware" Control on the PC - and see a "safe to remove" message before you do anything further.
(Make sure the file explorer is not focused "inside" the SD card E: (G:, H:, etc) drive, or this will prevent the "Safely Eject Hardware" control from working.
6) Press the trackball button again to turn of the USB-MS toggle in Amon_RA
If you do not correctly use the "Safely Eject Hardware" control on the PC, you will risk truncating or corrupting files that you transfer to the SD card. Be sure to pay attention carefully and perform the connection-use-disconnection sequence exactly as given above.