Some notes can be imported using Maximizer's standard import. Opportunities can not.
Importing notes and Opportunities can be achieved in most cases through the ODBC drivers - though you may need the integrators toolkit in order to work out the best approach. For this sort of import you will need some experience of working with database tables and SQL queries and may need to write a some program code (eg VB) to achieve what you require.
If its of interest.. we can undertake to do a one off import like this for you see
www.cabc.co.uk/Services/MaximizerData.htm Ian Wallace
CABC, Newbury