This list is not tailored but I happen to know who I will play. This is my first real list. Slann BEB - Cupped Hands, Standard of Disaplin, Focus of Mystery, Becalming, Lore master 21 TG - Banner of -1/-2 shooting 30 Saurus Warriors, FC 20 Saurus Warriors, FC Scar Vet, Miaming shield, Pendent of frenzy, GW, LA Skink Priest, lvl 2, Dispel Scroll, flying item 2 units of 2 salamanders Rare Stegadon 10 Camelion Skinks Deploy Slann/Tg in middle, Saurus warriors on each side. I expect 40 spearmen, 2 units of 12 crosbowmen, 2 hydra's 2 units of fast cav and a crap load of witches.
Which lore are you thinking for your slann? If your Scar Vet is using his great weapon, which he has to in 8th if he takes it, then the maiming shield offers no bonus attack the only thing it does is give him +1 to AS against shooting which a regular shield could do. If you need that +1 to AS in combat give him the Dragon Helm. Also I'd split the Chameleon skinks into two units of five.
I'll be useing lore of light. Bubbled buffs and 2 magic missiles that can have a extra 24 inch range? Also the reason for the shield is for the extra attack. I think I still get the attack even if I'm not useing it for the AS in CC. I like the idea of 6 S7 attacks.
If I remember correctly it would be an extra attack at base strength, or S5. The reason why you would not get that attack is that the shield can not be used in combat because the scar vet is forced to use the Great Weapon, which requires two hands so no shield can be used. If the shield can not be used its effects do not enter play.