Hello @feroxktm,
after a factory reset I’m having similar problems, mainly the solid magenta error.
I can put the Core in DFU mode, but the CLI cannot detect the Core:
>particle flash --factory tinker
Apparently I didn't find a DFU device? util said dfu-util 0.8
Error writing firmware...no dfu device found.
I think the problem may be a missing driver, where can I find the DFU driver you are referring to?
My Windows 7 Devices list shows a “CORE DFU” without a valid driver installed.
So I can’t flash my Core and install the updated firmware. And I can’t connect to the cloud. Help!!
Andrea
EDIT:
Why is Google so great…?
I found this: [Installing DFU driver][1]
So I could install the DFU driver and now I can flash from USB a new firmware
>particle flash --usb deep_update_2014_06
But I can’t find the .bin file anywhere on my PC nor on Github! 
It is missing
No such file or directory: Could not open file binaries/deep_update_2014_06.bin for reading
And this post does NOT help: [deep-update-source-file-for-spark-cli][2]
as the Github link does not work!
OK, I had to re-install the CLI (update did not work):
npm install -g particle-cli
DONE! Finally. feeew 
[1]: Tutorial: Installing DFU-Driver on Windows [24 Feb 2015]
[2]: Deep Update (source file for spark-cli)