I have an "affiliate address" used for receiving a small percentage from new sign ups, does this address automatically receive any coins that are sent to it? pretty much a similar question on a "refund address" should a transaction not go through this is where the refund would be sent too.....
Do i need to do anything?
You don't have to do anything. When they send the amount to your address, you will always get the money as soon as the transaction confirms in the network. You can re-use the same address multiple times and the coins will always be on the same wallet you control.
I didn't really understand the second question.
I've just deposited 0.011 of coins from where i bought them from and had to fill in the details in the "receive tab" so wondering about the 2 questions above if you know what I mean?
Those details don't really mean anything. All you need to share is the Bitcoin Address.
also, do you pay a fee for receiving coins in Electrum as when i click on "details" i see a small few that has been paid? 0.000374
The user sending the transactions is the one paying the fees. For example, someone wants to send you 0.05 BTC with a fee of 0.001, they will pay 0.051 from their balance and you will receive 0.05 Bitcoins.
p.s after you've bought coins and sent them to "Electrum" do you have to leave it running until the coins are delivered or can you slow it down and open it up later and the coins will be deposited?
No. You don't have to keep it open. You will always be able to receive payments and your coins will show up when you open the wallet again.