Back again. Finally. Have finished working my way through the reorg -- which, as comprehensive as it was, was only about half to 2/3 of my content. Eventually I'll need to organize the Studio content too, but that is just going to have to wait. At lest Studio seems to be decent enough to store the texture add-ons in the same place as the actual model instead of scattering everything about among half a dozen different Poser runtime libraries..
As you asked yes, I did run Disk Utility. I do that every few months or so. I also periodically run DiskWarrior to sort out directory glitches. The problem was coming from somewhere else. I'd been hanging onto SnowLeopard, due to a couple of legacy programs that I wanted to be able to keep access to. They wouldn't survive another System upgrade, since Apple did something fairly drastic under the hood with Lion. Which was back in 2011. Everything was fine in SnowLeopard -- except that I couldn't upgrade any of my Adobe apps beyond what would run in it. So I was 2-3 versions behind the curve and it was only going to get worse so long as I was using that computer.
Well, the video card bellied-up just about a year ago. I didn't know that it was only the video card or I'd have fixed that and waited until the end of the year to order a new iMac. If I had, the new one would have shipped with ElCapitan and I might have avoided the worst of the problems. Instead, I ordered the replacement in June and it shipped with Yosemite. Allow me to say that Yosemite is the WORST OS I have ever dealt with. And I've been running Macs since Classic OS 6.5 which didn't even run in multifinder as a default.
Admittedly, something that got ported in from my old system backup (which had odds and ends of stuff that had been floating around since 1998 still lurking in corners) probably destabilized it. But it was vicious. It hid my files, pretended my peripheral disks were empty and "lost" the contents of my projects disk twice, and then TimeMachine never performed a backup on that disk. Even though it *claimed* it was backing up the disk, there was never anything in those backup folders. I haven't noticed sweeping file loss since I upgraded to ElCapitan. I still don't like it as much as SnowLeopard, but I can work with it.
But I am still losing, or at any rate discovering, lost files. In the course of the content reorg, I kept coming across missing files. Not whole disks worth as with Yosemite, but in a sort of scattershot way. Things that I knew I had, knew were supposed to be installed, and which ought to have been there, and simply weren't. And more than half the time the old .rsr thumbnails were just gone.
SO. Back on topic; since I started the reorg DAZ has released another update to 4.9. Once I got my libraries on some kind of order I was intending to upgrade from 4.8. Now they've changed the game again. Is there anything I ought to know about regarding 4.9.2 as opposed to 4.9?