If the mod is loaded but you can't tell if it's working (you haven't seen pregnancies or move-in notifications), turn on logging in mc_settings.cfg by setting Logging_Enabled to "true" instead of "false".
If the mod is loaded correctly, this will give basic command-line function help.
From your home lot, you can open the cheat console with CTL-SHIFT-C and type "mc_help".
Make sure you have the checkbox on Game Options/Other checked for allowing script mods.
You can look in Game Options/Other/Custom Content and the mods should show-up as loaded in the Script Mods section.
If you use an earlier version, the ts4script extension may not be recognized and the Sims 4 will not detect the script mods. This has been tested to be working with GTW, OR and the patch released September 24,2015 – PC Version 1. This is from the troubleshooting section of the mod page: