So, every time I relaunch the MoP client, I get a message about whether I want to start the .EXE , regardless of whether I uncheck the box that says "Ask this every time". Additionally, once the client is up, every time, I have to agree to the ToS, put my Username and PW back in (which it doesn't save, even if I check the box), and choose the realm.
From the sounds of it, you need to enable read AND write permissions on your launcher. Otherwise, it's using the default client state. I have a Mac so I can't provide you specific instructions on how to do this but there are plenty of resources online for how to do this.