1. Mount boot.wim file
Dism /Mount-Image /ImageFile:”D:\DeploymentShare\Operating Systems\Windows Server Technical Preview\sources\boot.wim” /index:1 /MountDir:D:\offline
2. Copy the dism.exe and DISM folder from the Windows 10 Technical Preview boot.wim file to your deployment share, in my case D:\DeploymentShare\Tools\x64.
The dism.exe file and DISM folder are found in the X:\Windows\System32 on your boot image (once booted), or D:\Offline\Windows\System32 if you just mounted the boot.wim.
3. Unmount the image|
Dism /Unmount-Image /MountDir:”D:\Offline” /Discard
After copying the files, add two run command line actions to your Windows 10 Technical Preview and Server vNext Preview task sequence after Preinstall – Enable Bitlocker (Offline)
Copy WTP dism.exe
cmd /c copy %deployroot%\tools\%architecture%\dism.exe x:\windows\system32\ /y
Copy WTP DISM subsystem
cmd /c copy %deployroot%\tools\%architecture%\dism\* x:\windows\system32\dism /y
5. Deploy Machines