You need to learn a little more about what codecs are. .MOV is just a container...QUICKTIME container...that can be one of a few dozen codecs. Most of them are not editing codecs. What codec did you export as in MPEG STREAMCLIP? It defaults to Apple Motion JPEG A...which isn't something FCP works with. You need to convert to an editing codec. Look in the FCP Easy Setups to see your options. If this is 720x480...you use DV/NTSC. If this is high def, then use ProRes.
Shane
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