When I try to add content to sub items in the menu, the CMS seems unable to expand items and tries to load them for some time and then breaks the left panel in the CMS.

I'm concerned that either I'm doing something seriously wrong or the CMS is perhaps not the same as the one I used last year some time? I have NEVER had this problem before using Silverstripe. This is a very simple task I'm trying to perform and I've been struggling for hours.

If Silverstripe is mainly for developers, what CMS will be best suited for website authors?

Uploaded are a screen shot to better explain the bug. Or

Something looks very very strange with that tree. How many pages do you have under Multiply Users? Ive seen 100+ pages and the tree still 'works'. Ive never seen it try and do the loading screen!

I have 2 pages under Multiple users but it seems to happen for all 2nd level pages.

# Multiple users
* Sponsor
* Transfer

Are those 2 pages a Special type? or have any custom code attached to them?

Their page type is 'Page' and currently have neither content nor custom code.