Some community made syntax highlighters exist that can be used. Currently, they are only available for Notepad++.

In order to use the xml file, follow these steps. Go to the language menu, drop down Go to the user definined language menu Open the Define your language… menu.

You should see this menu:

Click the import button and find the xml file you downloaded and select it. A little pop up should inform you of success. Once that's done, go back to the language drop down and click the 4RPL that shows, when editing a 4rpl script. And you're done!