Open the registry (press START, select Run, write regedit and press enter) and navigate to HKEY_CLASSES_ROOT\.w3g. On the right site there should be a string called (Default). Memorize the value (normally it should be Warcraft3.Replay). Now navigate to the key (folder) with this name in HKEY_CLASSES_ROOT (for example HKEY_CLASSES_ROOT\Warcraft3.Replay).
Now go to shell, then open and finally command. There's another (Default) string, open it.
This string should be of format: path of RK in quotation marks, space, "%1"
After "%1" you can add feature parameters (a list of all possible parameters is following) to enable the feature on the next run of RK. If you had any problems with not existing keys or values, try reinstalling RK.
This feature modifies any chinese or russian name which would result in an empty string. Such names get replaced by Player#, where # is the slot number of the player.
Feature parameter: -names
There are two features. The first one applies team members similiar colors (e.g. red and orange) and high contrast colors to different teams
Feature parameter: -contrast (alternatively you can also use -colors)
The second feature also applies high contrast colors to different teams, but team members are colored the same.
Feature parameter: -teamcolors
Here you have four options. The first one removes all chat messages from observers/referees sent to all chat.
Feature parameter: -noobsallchat (alternatively you can also use -chats)
The second feature removes all observer/referee chat messages.
Feature parameter: -noobschat
The third one removes any message sent to all chat.
Feature parameter: -noallchat
The fourth one removes any message sent in the game.
Feature paramter: -nochat
Warcraft III gets executed in windowed instead of fullscreen mode.
Feature parameter: -window
This feature has two different modes. The first one forces RK to hide all informational messages (like "map was adjusted..") and just errors and questions are shown.
Feature parameter: -silence
The second one supresses every message, means RK runs completely silent (even questions are not asked, so occurring errors cause no interaction with the user).
Feature parameter: -totalsilence