The sole fact that a person is no longer being prosecuted in his home country does not guarantee an entrance into Switzerland respectively the Schengen area without complications. Critical are the inscriptions in the Swiss and/or European data bases where the person entering Switzerland respectively the Schengen area is not allowed to be publicised for arrest or refusal of entry.
This factsheet (PDF, 12.9 kB) explains how to access the relevant information. Please note that this Embassy is not involved and able to assist you in this process.
In case of a conviction in New Zealand, you also have the possibility to inquire with an attorney at law in order to find out if your conviction has been registered in a Swiss and/or European data base.