Which version of FM are you using? I can't remember which but one of the v revs of v13 (v2/v3?) added a checkbox when importing to 'preserve external container storage'. It sounds like that is what you need.
That solved it perfectly.
My clients are predominately Windows based and this client is running a number of xp machines so I have not been able to roll out 13 to them. I have been using 12 for the imports and did not realise the additional option was there in 13.
One of the joys of this business is you never stop learning.
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