Yosemite "problem resizing Core Storage" upgrade error?

Question

Not a great amount of luck upgrading from Mavericks to Yosemite here.
Download and start install, restart, see the progress bar, then the install screen with "about 18 minutes remaining". It moves along, and then boom...
OS X could not be installed on your computer
A problem occurred while resizing Core Storage physical volume structures.
Quit the installer to restart your computer and try again.
Restarting several times, as well as returning to Mavericks and trying again has so far failed. Live Chat suggestions of verifying and repairing disks and trying in Safe Mode also unsuccessful.
3TB Fusion Drive has over 450GB free space, just the single "iMac" partition within the Macintosh HD.
Any help greatly appreciated! Otherwise looks like it's a wait to see if a fix appears...
iMac 27-inch, Late 2012
3TB Fusion Drive
3.4GHz Intel Core i7
16GB Memory

Answer 1

http://de.wikipedia.org/wiki/Fusion_Drive
Fusion Drive is a technology developed by Apple Computer Engineering, with a SSD and a mechanical hard drive be connected to a logical drive. [1]
Description and function [Edit]
Fusion Drive called Apple a technique in which an SSD and a mechanical hard disk are transparently connected to a logical drive. The user sees the combination as a single drive. [2] With Fusion Drive is also in large storage volume can be benefited at a moderate price of the speed of the SSD.
Fusion Drive connects not only two physical drives into one logical, but still used in addition to a technology that tiering is called. When tiering, in German as "staggering", data on frequently accessed, the fastest drive (SSD here) saved, the other to the slower, here on the mechanical drive. What data is stored where, the operating system decides on the basis of a thorough analysis of the data access itself and can not be influenced by the user. Optionally coated the operating system in the background to data. The operating system itself is always on the SSD. [3] [4] tiering is used in mainframe computers for some time, with Fusion Drive this technology now comes for the first time in a personal computer for use.
Fusion Drive must not be confused with conventional hybrid drives. While in the latter case the SSD part only serves as a data buffer and all data is ultimately always stored on the mechanical disk in Fusion Drive SSD is a full-fledged part of the logical drive (except a small part of 4 GB [3], which also serves as a buffer).
Fusion Drive is since November 2012 integrated with all new Macs with SSD and mechanical hard drive. [5] The first corresponding Macs were equipped with a 128 GB SSD and a 1 TB or 3 TB of mechanical hard disk. [6] Currently (April 2013 ), Apple provides no utility available with which Fusion Drive install on older Macs could. But this can be done via the terminal, this requirement is OS X 10.8 Lion Mountain. [7]