FYI, with Excel 2003

For a Range with 35 areas, there are 271 bytes in the string:
This was not allowed.
A4:B4,C4:D4,E4:F4,G4:H4,A10:B10,C10:D10,E10:F10,G1 0:H10,A16:B16,C16:D16,E16:
F16,G16:H16,A22:B22,C22:D22,E22:F22,G22:H22,A28:B2 8,C28:D28,E28:F28,G28:H28,
A34:B34,C34:D34,E34:F34,G34:H34,A40:B40,C40:D40,E4 0:F40,G40:H40,A46:B46,C46:
D46,E46:F46,G46:H46,A52:B52,C52:D52,E52:F52

So, I tried 34 areas with 263 bytes, again, this was not allowed.
A4:B4,C4:D4,E4:F4,G4:H4,A10:B10,C10:D10,E10:F10,G1 0:H10,A16:B16,C16:D16,E16:
F16,G16:H16,A22:B22,C22:D22,E22:F22,G22:H22,A28:B2 8,C28:D28,E28:F28,G28:H28,
A34:B34,C34:D34,E34:F34,G34:H34,A40:B40,C40:D40,E4 0:F40,G40:H40,A46:B46,C46:
D46,E46:F46,G46:H46,A52:B52,C52:D52

So, I tried 33 areas with 255 bytes, this was allowed.
A4:B4,C4:D4,E4:F4,G4:H4,A10:B10,C10:D10,E10:F10,G1 0:H10,A16:B16,C16:D16,E16:
F16,G16:H16,A22:B22,C22:D22,E22:F22,G22:H22,A28:B2 8,C28:D28,E28:F28,G28:H28,
A34:B34,C34:D34,E34:F34,G34:H34,A40:B40,C40:D40,E4 0:F40,G40:H40,A46:B46,C46:
D46,E46:F46,G46:H46,A52:B52

I then finished up with the remaining 2 areas, used 15 bytes.
C52:D52,E52:F52

I looped, using each range object to do the necessary needs.

I need to try a case that has more than 66 areas.