I'll give this a shot, I'd like to have everyone using their own showers if possible, spending the money on shower heads, drains and pipes then not having them use them is frustrating. I could use the showers for other things as well instead of a room with shower heads that rarely gets used. They are getting upset because they don't shower, but ots not because I'm not trying to provide them the opportunity.
AHHHHHHHHH. Regime timing! @Skierky, you might be a genius. AI will always move to the nearest security compatible object to interact with, whether that's showers, toilets etc. Lockdown directly before showers, or showers directly after sleep (or a combination of the two!) will sort this right out.
Nat D11
That's how I set my regime. I see a lot of posts asking for the perfect regime and I learned you have to build your regime around the prison. I have showers at the end of my cell blocks and the canteen beyond the showers. Regime is sleep, shower, eat, yard and then work. The yard is central in the prison so from the yard everyone can branch out for work areas. Minimize walking time by minimizing distances between key areas!
I have my cell blocks set up so that the 2 cells on the end are actually a communal shower. The prisoners wake up, leave their cell and head to the nearest shower which is at the end of the cell block. Then at night I have an hour of lockup before they shower again. My medium security wing, for instance, has 8 cell blocks and each block has a shower at the end of it.
Here is my set up for 2 cell blocks side by side