I am not too ambitious about the accuracy, at least not at this moment.Here is the quick win that works. I believe it's not too efficient since I was not using blob object. I still need to figure out how to use it. On the other hand there are couple of unreadable characters at the end and this would need to be taken care of, as well as the plain text file that I would need to somehow prefilter and exclude from the processing.
In another words - this works but it's very spartan and not for further publishing.
Const ForReading = 1, ForWriting = 2, ForAppending = 8
Dim fso, f2read
If scriptColData.col <> "RealFTExt" Then Exit Function
If scriptColData.item.is_dir Then scriptColData.value = ""
Set fso = CreateObject("Scripting.FileSystemObject")
Set f2read = fso.OpenTextFile( scriptColData.item.realpath, ForReading)
scriptColData.value = f2read.Read(5)