To load the scripts:
1. Start Reaper
2. Press F4 for the actions dialogue
3. Tab until you get to the New Action button
4. Press shift space and a context menu appears.  Arrow down to Load Script.
5. An open dialogue appears where you can browse and select a LUA script file

To use the script:
The scripts appear as entries in the action list once loaded.
Run them and they will speak notes associated with selected items or selected tracks.
If you are going to use them often probably best to find a keystroke to bind them to.