In fxWeb7 themes are cached on the server. To force a refresh to a theme, editing theme.xslt (or any of the other theme stylesheets) is not sufficient, you have to edit default.xslt as well. This forces the cache to clear and will then render the revised theme.

The setting in the config file controls this feature.  Clearly it should be set to false on all developer machines in particular if they are developing the XSLT.  It has considerable performance advantages when set to true as there is then almost no disk activity.