1. Backspace or delete working until i turn numlock off. This is an old mathematica bug fised in recent versions. The Mod2 key is probably mapped to your Num Lock key. If the Mod2 keysym is mapped to Num Lock, hit the Num Lock key to turn it off. Depressing Mod2 turns on an undocumented feature of the X front end - global selection. When global selection is activated, the mouse pointer will change from an I-beam to a hand. You cannot place a text edit cursor within a cell in this mode, but if you select a cell of a given style, then all cells of that style will be selected. To avoid this situation in the future, simply remap Mod2 to another key using xmodmap or some other keyboard configuration utility. Notes It appears that by default Mandrake Linux 8 sets the Num Lock key on and maps it to Mod2. Therefore, it is suggested that you remap Mod2 to another key as described above. source : http://support.wolfram.com/mathematica/systems/linux/general /configurenumlock.html If you want to ...