Can I expect release of stable BOINC version for Windows 8 before Windows 8 release in august/october?
Any ETA on this?

When will a version of Boinc that installs on the Windows Release Preview be available? There appears to be a problem creating a boinc admin group or abiding by the default local group policies. I really don't want to have to dive into Maicrosoft's policy schemes just to run boinc!

There has been a version of Boinc compatible with Win 8 since around the 3rd May, see the BOINC 7 Change Log and news thread:

Preliminary Change Log 7.0.26 --> 7.0.27:

WINSETUP: Fix long standing installer bug where we were attempting to add the boinc_master account to the boinc_admins group when installing in the non-service install mode. boinc_master is only created during service installs. This was causing a setup failure on Windows 8. As far as I can tell it should have also been failing on Win7 and Win Vista.

Claggy

Been running Boinc-projects on several machines, but now having problems installing Boinc on a Windows 8 Release Preview (Build 8400) (64-bit Intel processor).

Trying to install version 7.0.28.0
Seems to run through the installation process just fine. I see a Boinc Manager as a "tile" on the metro side, but when I click it reverts to "desktop" side, something runs, but gui never opens.
The Boinc client is visible in background processes, I've given it admin priviledges and have also tried running it in both Vista and Win7 compatability modes.
I can also see a boinc_master local account in users, and I have given it admin priviledges.

Can't find any log files in either the program files boinc-directory or in the users\boinc_master-directories

Anything I could try next?

C:\Programdata\BOINC\ is the BOINC Data directory where BOINC writes all its data to. It's a hidden directory, so either fill the path directly in Windows Explorer, or tel Windows Explorer to show hidden files and folders.

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