I was able to export out of FCP to PDW F70, But I did not format the disc. Try it without formatting.
Note: I only had CBR output choices at 25Mbs, there were no settings for 35Mbs, The Sony folks said I should have HD output settings for 35Mbs. Can you check to see if you have these settings for HD 1080 24p
@ 35Mbs VBR.
I can import @ 35Mbs just fine no export to deck at this settings only @ 25Mbs CBR.
Regards
Steve