*This message was transferred with a trial version of CommuniGate(r) Pro* Good news: It works! I just wasn't being patient enough earlier -- when I turned on the debug output this morning, it became clear that the scanner had in fact *not* locked up partway through the scan, but that it was simply pausing to transfer data. Repeated invocations do *not* cause the scanner to lock up.
It looks like the performance issues I'm experiencing are in large part due to my host system only having USB 1.1 support. I'll be trying to fix that shortly. For the record, the scanner in question is a fi-4120C2dj.
