We got married over there too, Congratulations on the upcoming weddings 
We went to that court house for our licence too - when you go through the main doors they have a security check point like at the airport where they might wave the wand thingy over you and maybe scan your handbag. Then we just went to the relevant office and got in the queue - just like a post office
then you show them your documents and forms and then you have to do the oath and pay etc.. and then off you go! 
You'll be fine, I was worried beforehand too but it all went smoothly 
Good Luck 
We went to that court house for our licence too - when you go through the main doors they have a security check point like at the airport where they might wave the wand thingy over you and maybe scan your handbag. Then we just went to the relevant office and got in the queue - just like a post office
then you show them your documents and forms and then you have to do the oath and pay etc.. and then off you go! You'll be fine, I was worried beforehand too but it all went smoothly Good Luck 
