Hello, You are correct. I couldn't get into Mon Cheri. I must admit that I have tried again and did get in. I was dressed fine the first time, but it is possible that I had not done something (like shower). I believe the message I got was that I wasn't wearing nice clothes or something to that regard. I then clicked on the clothing icon and it said (and still does) that I am wearing normal clothes. That is where I got the term "normal." I assumed (I guess incorrectly) that that meant I was not dressed nicely enough. Anyway, now I got in, so that is no longer a problem.
I also have the exact same problem with the "addedflavour" mod (when going to the city with the mom). This problem still exists, but is no doubt a problem of the mod and not the game. The message I get is, "If you were wearing some nice clothes you could go out to the city with your mom." I am well dressed, clean, hair combed, with makeup, but can't go out with the mom.
Thank you for your response. Take care.