content panel problems

I'm trying to use a html file for the content of my content panel but it shows blank. Is there something I'm doing wrong? Please help.

KoolMoves makes it seem so simple to upload a html file into a content pane. I tried it but when I play the movie my content pane is blank. Can somebody please help with this.

KM can show text enriched with html tags but the Flash Player only supports a limited amount of tags. If you use a normal unaltered html file, there are probably a lot of tags the Flash Player can't handle.
The subject of what html tags are supported has come up several times before. If you do a forum search, you can find what tags are supported.