only works on C:

[Paruccone]

an option should be available for it not to use C: drive for storage/temp.

manually setting $mainOSDrive doesn't help, script keeps referring to system drive here and there:```

The operation completed successfully.
Mounting Windows image. This may take a while.
ERROR: The system cannot find the file specified.
C:\tiny11\sources\install.wim: The system cannot find the file specified.

because of 
$env:SystemDrive being used later on instead of $mainOSDrive

[Karl-WE]

There a broken logic that it sometimes uses $ScratchDrive as specified by parameter which defaults to $env:systemdrive
while other commands using $env:systemdrive regardless.

I will address these for consistency in PR #268
Requires quite some testing :/

[Karl-WE]

@Paruccone this one can be closed.
@ntdevlabs
Solved with #268