Easiest RAID configuration to recover data if ReadyNAS fails

Hi, I did everything up to bullet point 5. After inserting the 3rd hdd the nas recognized it, the number 3 lighted up and a message appeared on the LCD panel about it. Then the LCD went blank for a while, with the act light blinking. I waited for it and refreshed the webpage with the volumes tab. Now the LCD panel is blinking "data: DEGRADED" and the volumes tab show that a rebuilding is in progress and that disk 1 (200GB) is red, while the other two (320GB and 3TB) are green. It also changed from RAID-1 to RAID-5 (still X-RAID).

It is really possible that this 200GB disk has problems; I vaguely remember ditching it for random disconnects, but I'm not 100% sure. I won't be using it really, it was just for this test. Rebuilding is progressing, probably because it was a RAID-1 so no problems. However, I probably won't be able to progress with the test since I now have only 3 healthy hdds available. I have another 200GB that I know is healthy, but it's not here atm. I'll try to get it tomorrow and substitute the problematic one. I can also buy some 2.5" to 3.5" adapter and use some spare laptop hdds I've here.

edit: another problem... the volume was resized for 320gb. I'll probably have to start from scratch.