Thanks, everyone.

I've rebooted (several times) since installing Quicktime.

I've confirmed that Quicktime is working by viewing a movie file with it.

I'm running this on a Dell Inspiron 8600 with a 1.7 GHz Pentium processor with 1.00 GB of RAM. The OS is Microsoft Windows XP Professional version 2002 with Service Pack 3.

BIAB is now recognising that QuickTime has been installed, and gives the correct version number.

If I try to generate .mp4 files for all files in the BB2Go folder, I get the message about the Rendering being complete for the first file, and BIAB then plays the file until I click OK, when it moves on to the next one and plays it. No rendered file of any sort is left in the BB2Go folder.