Some integrations requires two separate fields for the full name

another problem is importing names the freshbooks intergration wants one field and salesforce two fields and I need to connect to both?

Have you tested just using the full name field under quick tools? I think it would come on Salesforce just one field once you map it on the integration wizard. 

By the way, Salesforce allows custom field too. You can create a single full name field on Salesforce and use it on the integration.

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