Hi, thanks for the reply,
I have only just bought the galleries - within the last two weeks so I assume they are bang up to date? I definitely copied all files as the packages were unzipped directly on to the server and simply 'mv'd into place. They were also downloaded and installed separately as I bought, installed and imported on to one before buying the other.
installs are on the same server, although it's pretty standard up-to-date CentOS. The caching enhancements are x-cache (correctly with different prefixes) and vboptimize. Could either of those be the problem?
I can of course hard code in the two variables if necessary, although is it likely that other less obvious problems are also happening?