Thank you for help and suggestions. You are and have been a real help with some of my problems including this one.  I already did a rant in another thread about 're-upping' this Jan, as I usually charge for doing diagnostic work for other organizations. Support is usually pretty good, but it's probably another weekend with FLS and BiaB until they will be able to get back to me. Just saying that this is my experience.
 
And I was just getting the W10 sys stable enough to play with SPro using the new HDMI amp, too. We'll see.
 

Got it installed and same error. I'm running out of time this am, but will try to get to Support and report back, after they do. I'll try disabling the local help since I've got some BW now. That might work for a bit this afternoon. 
 
I'd hoped I was doing something silly (yet again) and the forum would straighten me out. At least it is repeatable. Those intermittent things are tricky.

Very Short Story: Sonar Help seems to presume I have more than 1GB available for temp files. I had placed my temp files on a RAM disk since they are 'TEMPORARY', and generally small and non-persistent. Any guidance on total space required for temp files needed by Installers, Help and Sonar itself when active?
 
It took the best part of this weekend to sort this one out. 
 
Now at the onset, let me state that this is not a problem particular to Sonar.
Both FLS and Biab behaved similarly when trying to get their help files.
However configuring installers to use their own dirs for temp files for extraction is pretty common (ie. zip tools) if more than 1GB is needed.
 
However, it's becoming pretty clear to me that the best option for running Sonar is a BIG C: drive (of whatever sort). Another poster reporting 'All's Well' seemed pretty happy with his 500GB SSD at C: with Pref/Frolder options elsewhere. I still run X1x32 for my legacy stuff, and there were interactions between Pref settings between x32 and x64 settings in X1. I don't recall checking for interactions in Prefs between X1x32 and SProx64. Many of the older CW VSTs also need space on the boot drive. 
 
If I get any guidance about storage requirements, I'll let CW post them.
 
OT comments:
I might get big SSD C: someday, but not until all this OS stuff settles out. That's one example of my reference to a 'dedicated' PC for the DAW. 
 
Oh by the way, it was an update to a mobo prg that controls the RDisk, that set me on the right track. I'd seen this problem before and disabled the RDisk, but some settings somewhere seem to have persisted until I fixed the RDisk with an on/off cycle once again. Oh yeah, it's ReStart now rather than ReBoot. Progress from M$oft at last, and probably a reference to the Start Menu. Once bitten, twice shy of 'updates' as they say ...
 
It's the unintended consequences of interactions that generate failures, in my experience.
 
Time to play!
 
 
 

Well, for Sonar Platinum, I did everything through the new Cakewalk Command Center (CCC or C3), but FIRST, after installing and launching THAT, prior to doing any of the installs of the Sonar stuff, I clicked on the thing near the upper right corner of the UI screen for the Command Center, which opens up its Settings dialog.
 
There are path settings you can change in there, for where it stores all of the installer files, as well as where to put content and VST plugins.
 
Additionally, if you wanted it, there is a check box for doing Verbose Install Scripts, where you would be presented with the regular sorts of choices you would make for a typical install, and you would choose that to be to have more control over installation choices that would otherwise be made by the Command Center - such as telling the Sonar installer that you would like to install a 32-bit version, in addition to installing a 64-bit version.
 
Even though I had things like Dim Pro and Rapture already installed, I let Command Center go ahead and re-download and install everything, so that it would all be brought under its umbrella for future releases and updates.
 
I hope the above is helpful, and I hope all is well with your setup and your world.  :)
 
Bob Bone
 

I'm still thinking a little about this.
I've setup those settings last Feb, though it took 2 tries find them. I'm easily confused. 
Still excellent advice.
 
This may be well outside anything CW can change and may be the result of some MS help functionality. Still, installers, help, and not just those IE caches wish to rent temp space on my SSD for free? REALLY!
 
I'm just happy to not be on 1Mb/s no more.
 
OT: Now, I always use local help and still:
1) Each time I press F1, am I generating ~1GB of temp data on my SSD?
2) Each time I go to a different help page, is this another ~1GB? 
 
I'm just speculating on actual sizes and want to play with Sonar today. Might be just a 1/4 GB.
But MS wants to put this on mobile devices?
 
Well, let's just call that topic A.
 
 Of course, there may just have been misplaced references to the no longer existent B: (RDrv), rather than file size issues, but the drv doesn't show in MyComputer (or whatever MS calls it these days, mine is C....D....). So there shouldn't be any other users, or so I'd think. 
 
The lack of error diagnostics is also a bit disturbing. No msgs reported, even hints of errors. (My favorite is from MS itself "Something Happened! System install has failed.")  May you never see this msg as I have.