Just to be clear, the reason I reported this here is that I don't think this is a Numbers bug. Numbers opens Excel files just fine. It opens these files fine after they are re-saved by Excel.
I think this is a Filemaker bug . . . the Excel file it produces has something strange about it.
Thank you for your post.
I am unable to replicate the problem using FileMaker Pro 9 and Numbers 09. I would like to get a copy of your database file so I can test it further here. I have sent you a private message (top of this page - right side - X Messages) with instructions where to send the file.
Also note that a CSV export opens fine in Numbers.
I've also tried exporting different data, and in different sort orders. It seems that it's the text data that misaligns, and usually around the same place, i.e. row16, then row24
I received your file and I was able to replicate the problem. I switched to FileMaker Pro 10, and the resulting exported file (I used .xls and .xlsx format) is correct when opened with Numbers. I have sent a screen shot to our Technical Support liaison, and you should receive that shortly.
Although this appears to be working correctly in FileMaker Pro 10, I do not see any reference to this being a problem with any previous version of FileMaker. I seriously doubt we will revisit FileMaker Pro 9 to fix this problem, so use the CSV export.