Code:
startLine = 5
endLine = 20
fileName = "C:\Program Files (x86)\Microsoft\Small Basic\SmallBasicLibrary.xml"
For i = startLine To endLine
lines[i] = File.ReadLine(fileName,i)
EndFor
For i = startLine To endLine
TextWindow.Writeline(lines[i])
EndFor
I corrected and uploaded your extension, not sure how it will help since it does less than the SB code above ZSExtension.