Hi,
I am from Bangladesh. I have more than 6 years of development experience. I have worked on XSLT/XSL for data exchange. If you are interested to see I can show you a few my related work with XSLT/XSL.
Basically here are three part as you describe, number one is exporting data to XML from Filemaker, number two is setting the mechanism to view XML data in Excel and number three import data from excel to Filemaker.
Do you need all of the mentioned things? or only export Filemaker data properly to XML using XSLT/XSL?
To export data from Filemaker to XML using proper XSL may take up to 10 hours (max). Actually XML to Excel viewing is new for me, but I have knowledge about it. Importing data from Excel to Filemaker may take another 10 hours (max).
Ready to discuss/communicate in other faster media as necessary. Waiting to hear from you...
Thanks for your time.