I did the same thing and I did get it fixed. Now that you have 0.5 downloaded, flash back to 0.4 long enough to download the kernel. Download but don't install. Once you have that downloaded, boot to recovery, flash the v0.5 file and then flash the kernel. Reboot and Viola! I had the same problem you did but I still had 0.4 on the SD card. Flash back, download Toolbox, download the kernel, and then just flash to recovery and install both that way. Runs like a champ now........ Hope this helps!
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