Thanks, that was helpful but not yet the solution.

I removed in the Apache httpd.conf  js and css from the filetypes that are to be served from the server and got in a lot of other trouble because there were other files missing, so obviously Apache is trying to serve the js and css files from the server, which would be fine for me. This gets us to the point " it is served by Caché server and depends on settings of corresponding CSP application on Caché server side ". In the CSP application the location of the csp-files is set to

c:\intersystems\cache2015\csp\jbsscan\

this would give as location for my files:

c:/intersystems/cache2015/csp/jbsscan/jbsscan/stylesheets/style.css

c:/intersystems/cache2015/csp/jbsscan/jbsscan/stylesheets/style.css

or is there an other setting which influences this.

Anyway, I put the files in this location. It didn't  help, the functions and styles of these two files are still missing. But something happened, the app got really, really slow.

Any ideas how I should proceed?

Yes the csp app is working with a webserver on the same Computer.

The snippet above has relative paths /jbsscan/stylesheets/style.css and /jbsscan/javascript/javascriptScanner.js, where could I find absolute specifications which overwrite These?