How can I change the margin settings in the pages inspector to make them more specific for label templates. I need margins that can be set to hundreths of a centimetre not just tenths.

When I write 2,12 cm in the margin field the Inspector accepts it. You could also try changing the from centimetres to pica or points

I doubt you need hundreths as you would not even be able to measure that and the printer doesn't hold the paper to those tolerances.

fruhulda is right. Pages accepts higher measure but rounds it in the measure field.

If you want absolute accuarcy you need to set your measures to points. Everything else is being recalculated.

Peter