Sorry to hear some folk are still having trouble.
Could you tell us which version of the site you're using (desktop or mobile), what operating system you're on (Apple, Windows, Android etc), and what browser you're using (Internet Explorer, Chrome, Firefox etc)
As a general rule, if you're on Internet Explorer Version 8 or earlier, lots of features of Mumsnet won't work well. If that's you, we really recommend you upgrading to a more recent version of IE, or even (preferably) Chrome or another browser.