Bruno,
It looks like an issue is with the beanRefContext.xml. You do not have to add the application's *-web.xml to the beanRefContext. It's a special context that isn't supposed to be handled by Spring, but by Red5 itself. In fact, none of the files are necessary except for logback-oflaDemo.xml and oflaDemo-web.xml. Once I removed everything else, the oflaDemo gets the streams from the proper directory every time.
I haven't tested it yet but I'm going to guess that's why you were also having problems deploying multiple wars.