if you converted the wim to wmc you'll get a windows8.1 pro wmc with startmenu. would be interesting if the tokens.dat applies
ThresholdInternal and ThresholdOptedIn are the reg values required to enable the enhanced build update UI
It's for adobe flash and IE component it has companion update kb3002675 which updates WindowsUpdate Core
Code: Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsSelfHost\Applicability] "BranchName"="fbl_release" "ThresholdRiskLevel"="high" "ThresholdOptedIn"=dword:00000001 "ThresholdInternal"=dword:00000001
That worked. You can change the "update speed" to fast, but when downloading the preview build it finds, I'm getting error 0x80246017. So this may not be useful unless you're connected to a MS VPN or something.
2014/9/13:6:35:53.267 6.4.9810.0 (fbl_lad_dev01.140518-2041) <- 18 May 2014/10/1:23:39:1.104 6.4.9841.0 (fbl_release.140912-1613) <- 12. sep