[dnanian]

I don't believe the Migration Assistant will allow a sparse image as a source, Niek (at least at first boot, because there's no way to mount it). It might allow it to be used when run "after the fact", though, if you mount it and indicate it's "another volume on this Mac".

What I'd probably suggest is using something like iPartition to partition the LaCie "live". I think you'll end up happier. Or, I'd just do an archive-and-install rather than a clean install.