There are several reasons for this.
Frequently, the program undergoes changes that may not get pushed out to all users at once. It may be that the wiki version is more up-to-date than your program.
Users and supervisors can change the settings to display or hide certain items. Your CATS settings for fonts and colors can also dramatically change the way CATS looks.
Occasionally, users are given features that are not displayed in previously created wiki pages. Overhauling all images at once is usually not feasible.
Finally, there may be an error in your program with either display or behavior. Check with New Data Systems if you suspect this is the case.