<<< I have connected a cat5 lead to the WAP and set it up as said, >>>
Erm, what have you connected the other end of the CAT5 cable to? A "Wireless Access Point", as its name suggests, provides a point of access for Wireless Network Adapters into a "wired" network. It would, for example, be plugged in to a "non-wireless" router so that it is converted into a wireless router. Your Wireless Router already incorporates a Wireless Access Point and to use a second one for improved performance, it would have to be connected by a long ethernet cable to one of your router's LAN ports.
If you are plugging a Wireless Access Point directly into a PC's ethernet port, it will *NOT* communicate with your router. In simplistic terms, think of Wireless Access Points as "Receiving" devices and Wireless Network Adapters as "Transmitting" devices - the two "Receiving" devices will not communicate.
A "Wireless Network Bridge" is the reverse of a "Wireless Access Point". Instead of letting Wireless Adapters access a wired network, it lets a wired network access a wireless one. In other words, plugging your PC into a Wireless Network Bridge would then communicate with the router's Wireless Access Point. Whether the wireless performance is any better than using the PC's WiFi adapter is another matter.
Example of Wireless Network Bridge - click here