When you exported your XML did you make sure to check the box that says “include master clips…”? Also I know that there are two different versions of XML, version 1 and version 2. FCP 5 exports a version 2 XML by default unless you specify version 1. If you are going to a program that will only import a version 1 XML it’s possible that you would lose some of your clips.
FCP editor
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