Import of 10_HKEY_USERS_DOT_DEFAULT.reg is working OK now. StartIsBack and PENetwork keys appear in DEFAULT Registry Hive.
Booting PE_19041_US_E.wim is OK.
But I have another issue now: In PE the Desktop background color is black instead of Wallpaper blue, which has to do with ACL I presume.
Originally the sequence giving good Desktop Wallpaper color was:
reg load > use SetACL to Take Ownership and Grant full access for TK_DEFAULT hive - Then Import Registry Settings > reg unload
I think I need to use reg import so that I have control over permissions.
================================================================
New version has issue with import of HKEY_LOCAL_MACHINE\SOFTWARE .reg files
In that case I get .reg.new files ........
I am surprised about ACL :
-offlinereg wnen modifying a hive does not care about ACL's : it just stands above ACL's
-winpe when accessing a hive runs as SYSTEM so normally is not affected by ACL's
Rather I'll compare a blank hive (open with regedit after the import and export to a reg) where you will import your reg file against the original reg file.
I just uploaded a new version fixing an issue with default @ values (it was importing an empty string).
Here.