Using procmon I made some progress with rapidinstall in windows 7:
Disallow traversing these junctions that point to their parent directories in windows 7:
c:\programdata\application data
%userprofile%\appdata\local\application data
I did
mkdir ..\fakedir
mv 'application data' ..\fakedir
(cygwin mv)
Filter these 2 directories to save time. winsxs has a ton of hard links, and $recycle.bin never seems to get cleaned up:
ignore c:\windows\winsxs
ignore c:\$Recycle.Bin