Yup, same problems here..
Tried it all. Disabled all my plug-ins (I dont have the seo, or the tinymce, or the flash plug-in) - nothing. cleared cache on the blog, and both on my browsers and my comp. Then tried the full delete and fresh install.. nothing works.
I do not have editing buttons on my editor, new or old posts.
The editor will only stay on what seems to be the HTML editor, and if I dare to click the HTML tab again the whole edit box collapses and wont come back until I refresh the page.
Also, on the little "Page options" button in the top right - I have to check the slug box every time anew.
Havent tried installing it on a different folder, didnt see a valid reason for that since I deleted the whole thing and installed again.
..There must be something more general behind this.
Any other suggestions maybe?