1. As I understand you can make one melee touch attack as a standard action. However you could also deliver a touch attack by hitting an enemy with your hand, or rather claws for natural weapons or an unarmed strike for a monk.
2. If so, would that apply to all your hands/claws? Is chill touch be cast specifically on one hand?
3. I do recall that casting another spell removes any held charges. If using magic items, potions or wands while holding a charge, does that remove your charge?
4. As for greater fang I'd like to bring an example.
You polymorph into a Four-Armed Gargoyle (minutes per level). You cast greater magic fang on each of your 4 claws (hours per level). As the polymorph spell ends, you lose your claws.
But an hour later you decide to become a 4 armed gargoyle again. Is the greater magic fang still applied to your 4 claws?
5. Not in the title, sorry but it's about haste.
First of all, haste and natural weapons. I can only assume it stacks. Can you select which of your natural weapons gets the additional attack?