If I am registered as a normal level user and log in and try to submit a blog entry the text editor does not appear - but if I log into the frontend as a super administrator I can see the text editor no problem.
Check the Mamblog Configuration from the component backend. Look at the Viewing tab. The setting to look at is Use the Mambo default html editor on frontend?. This should be set to Mambo default editor. If it is not try changing this.