My EFWS2900 was bricked completely after update to 1.5.2. Fortunately I got a replacement of the console. The new one updated to 1.5.2 without any problems. I suspect, that I had some old batteries loaded, which forced kind of a reset during update. This assumption is, because when I added the same batteries to the new console, it started to reboot after some minutes. As soon as I removed the batteries, everything worked fine again. As long as you can perform a hardware reset (remove the batteries, unplug power for at least a minute, then immediately after powering starts and all segments appear on screen, press WIND and PRESSURE at the same time for about 5 seconds), you could try to at least get a clean installation of firmware 1.5.2. For me, I have learned to remove the batteries, whenever I do an update again. But, may be, this is just electronic voodoo.