Self contained scripting

I'm familiar with importing an external reg file using vbscript on startup as follows:

Function OnFirstParentStart

ExecuteVirtualProcess "regedit /s C:\tmp\somereg.reg"

End Function

Is there a way to embed the *reg file in the virtual filesystem and execute it from there so the solution is self contained?

Example which does not appear to work:

Function OnFirstParentStart

ExecuteVirtualProcess "regedit /s %Personal%\somereg.reg"

End Function