@RavenLure So the shower/tub combos are working fine? You are just having trouble with regular showers?
Removing your mods and custom content for testing can be done fairly quick and easy. Just move the contents of your Mods folder to a safe location like a temp folder on your desktop or an external drive. Then delete the localthumbcache.package from your Sims 4 folder.
Disabling or turning off both mod/cc options in your Game Settings isn't enough of a test. Removing the mods folder without deleting the localthumbcahche.package file from your Sims 4 folder also isn't enough of a test. It all has to be done together.
Start your game and see if the showers are working fine now. As @Psychotps said, after testing make sure you exit the game without saving.
- If the showers work fine now, then yes it's probably an outdated mod or CC
- If they still do not work, then maybe it's just a routing problem
Please let us know either way. It's too difficult to recommend any further steps for you to try without first knowing if this problem is caused by mods/CC or not.
For the issue with Events not working properly for you, it's best if you could research existing topics to determine if what you are seeing has already been reported & if a fix has already been found. If not, then please start a new topic for that issue so we can focus on just one problem per thread. Add as many details as you can!
Good luck :D