This problem appears to be server side and prevents css style sheets bing correctly parsed by Mozilla based browsers.
Try This:
In your programe files open the Omnisecure folder.
Load file: oadmin.exe
Click: Web Server Global Settings
Click: “MIME” Tab.
In Vertual Input: text/css
In Actual Inpiu: “.css” – don’t foprget the dot.
Click: Add
Click OK.
Good re-boot required.
On my system this resolved the problem.