I managed to get the white screen as well after upgrading to the latest firmware (UFX: 351/141/340) on a powermac 8 core running snow leapord.
The unit had already been flashed to the latest firmware from a Windows 7 64 bit Sony Vaio but after recording a 27 track concert through DuRec we found that we could not get the files recognized by ProTools 9 on the above mentioned Mac (or any mac/protools combination of the 3 that we tried really). It gave a very obfuscated error about file location and then refused to load at all. This was never a problem with multichannel UFX files of any size from previous firmwares. ProTools was able to eventually load the files after converting them with the Mac version of the multichannel wave batch file processor but the audio had the continuous static sounding distortion of a file that has been interpreted incorrectly. These problems persisted for any subsequent DuRec recording tests we did to a selection of drives.
After converting the files of the original DuRec drive using the PC version of the multichannel wave batch file processor they all loaded fine into ProTools 9 on the Mac.
It was in the interests of fixing this strange file problem that we attempted to re-update the firmware from the Mac. When this resulted in the white screen we located an old firmware from June of this year and succesfully flashed back to this. All recording tests since have worked flawlessly.