The new Slack 14.0 slackbuild for XBMC 11 produces a package that works nearly perfectly.
The only problems I've noticed are the HULU and FreeCable addons from the unofficial BlueCop repository will not run properly on the Slack 14.0 slackbuilt XBMC 11. FreeCable simply fails to stream most content, while the HULU addon actually causes XBMC to segfault at the point of streaming content. The problem appears to be the default rtmpdump.
The simple workaround I've used to get the HULU and FreeCable addons working in the Slack 14 version of XBMC 11 is, after installing the slackbuilt XBMC package, to install the rtmpdump-2.4 package from the Slack 14.0 version of the SLAXBMC project, which package is available at: http://www.slackware.org.uk/slaxbmc/...slackware/xbc/
The package overwrites the version of librtmp present in the default XBMC installation, and the XBMC Bluecop addons function normally next time XBMC is started.
Hope this helps someone else.