My Edwin is now at level 11 and he only get level 5 spells, i mean he doesent have any level 6 spells isint that a odd ???

Not odd at all my friend. Just level him up one more time and watch those slots appear. You see, specialist mages get extra slots due to loss of some spells, but that doesn't mean they get EXTRA LEVELS too.

So its 6th level slots at Lv 12
...and 7th level slots at Lv 14

Did that do any help?

Yes thanks a lot mage

Good pal! Edwin is definitely the strongest npc mage in the game, i always prefer my main char as fighter or paladin and i cant live without edwin. Even in baldur's gate 1 hes one of the strongest mage as well as dynaheir, minsc witch. So many fireballs, and cloudkill my favorite espcially in killing those dragons. Beside his arsenal of spells his comments are funny on townspeople and among your party members.

Yeah i also have notice how useful Edwin can be. Including his the only pure mage in BG2