The light sequence is set to go off at random time. This is to stop people with experience of the system counting down from a set number of seconds and getting a better start than someone who doesn't know how long it takes for lights to change.
Not quite sure what other systems (functions) you mean, but probably.
For instance, if you didn't want times to show at each split, then delete the whole subs section for each time, such as
Sub SE_100mLineLeft ($userName) # Shows Blank Result Board ...... EndSub
Any other system/function you don't want; just a case of going through the code and deleting each of the subs, which are fairly self-explanatory in what they do.
Best to make back-up copy of whole script, and delete each subs code one at a time, testing as you go.