Seems like a question to ask Salesforce tech support rather than FileMaker as users here aren't likely to know what options and utitilites are available in SalesForce for importing data from an external file.
Ok thank you for your suggestion PhilModJunk, will keep this post updated if I find answers.
I know this was posted over 4 years ago. But wanted to let you know we can create a custom integration between Filemaker and Salesforce. Because of the nature of the two systems it has to be a custom project, based on tables and fields you would like to sync. We have set it up to sync daily. http://filemaker2salesforce.com/ Let us know if we can help.