This mod allows you to skip "Demolition Man" mission in a way you won't get frustrated.
If at some point you'd like to (at least try) complete the mission without this cheat, use my Complete Mission Loader.
I'm using a manual keyboard/ PC. I don't have a number pad. When I press "0", nothing happens. I have both the source.txt and the .cs file in file "CLEO" in E:Games/Steam/steamapps/common/Grand Theft Auto Vice City. I've open the .cs file with Sanny Builder (which is labeled for SA, does that matter?) but I didn't make any changes to it. What am I doing wrong?