It seems that you're using an outdated browser. Some things may not work as they should (or don't work at all).
We suggest you upgrade newer and better browser like: Chrome, Firefox, Internet Explorer or Opera

I'm playing IWD2 Classic with mods having started the game way back when. The last mod I installed then was to replace most of the goblins in the Prologue (Targus) with skeletons. I find this punishingly difficult, or else I've just lost my grasp of tactics in this game.

I started one character as a halfling rogue (the second halfling on the menu), which has preferred class Rogue (the third one does not). Since I have 18 INT I thought I could multiclass to Wizard / Mage and have access to spells - but after levelling up from Rogue to Wizard there is no icon with crescent moon and stars (see attached screenshot with the rogue/wizard selected). My single class Clerics and Sorceror all have the icon, and can cast fine.

I tried resting and then learning and memorising minor mirror image. No difference. Only the rogue skills appear.

What am I doing wrong?
This question / problem has been solved by Jigbyimage
You can change the buttons by right clicking on them. The button is not added automatically, you have to do it manually.
Thanks! I had completely forgotten this