Maciek created the issue

This is on a MacBook Pro with OS X 10.4.7.

When I drag a large number of files from Cyberduck (approx 5500 files) to a folder in Finder, Cyberduck starts the download (then stalls shortly after), and then Finder consumes 100% CPU on both cores. Both Cyberduck and Finder are unresponsive afterwards. Eventually, I have to restart Finder or even OS X to get back to normal.

Once this happens, Cyberduck will crash upon subsequent launch attempts. The only way I was able to get Cyberduck to launch again was by erasing Queue.plist which I found to contain 57000 lines of plain XML (perhaps using the binary format of plist would help?). Once I removed that, Cyberduck launches again without a hitch.