1,2,4 are very easy.I give you code for color comparison
Code:
Set ex=createobject("excel.application")
Set wb1=ex.workbooks.open("E:\Testing\Framework\Data\a.xls")
Set wb2=ex.workbooks.open("E:\Testing\Framework\Data\b.xls")
Set sh1=wb1.activesheet
Set sh2=wb2.activesheet
colorSame=true
For each c in sh1.usedrange
color1=c.font.color
color2=sh2.range(c.address).font.color
If clng(color1)<>clng(color2)Then
colorSame=false
End If
Next
ex.quit
Set sh1=nothing
Set sh2=nothing
Set wb1=nothing
Set wb2=nothing
Set ex=nothing