Not true.
I use Compressor all the time to convert to LT from my Flip.
The only reason Compressor would not give you the option to convert to LT would be if you were running a version of FCP prior to its inclusion. ProResLT is included in the Standard Quicktime Presets.
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And to the OP, Make a copy of the ProRes LT preset then change the Audio setting to convert the Flip's audio to 48khz.
Save it with a useful name (Flip2LT) and it will show up in your Compressor's Presets CUSTOM folder.
Next time you need to do this, drop in your clips, drop the custom preset on the clips and let Compressor run.
Spend some time reading about Quickclusters if you have a multi core Mac (4, 6, 8 or 12 cores). You can significantly reduce conversion time.
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