I have done what you are asking about using 1900 series and 2030 APs. I am not sure if the 1800 series has the same capability but I assume they do.
Here is what I did:
1) Configure one specific port (Ge24) on our switch to use VLAN 14, untagged (the choice was random, 14 was available).
2) I tagged any ports our access points were connected to on the switch (Ge13, Ge14) with both VLAN 1 (our Corporate VLAN) and VLAN 14 (guest VLAN)
3) Connected the "guest" internet connection to port Ge24.
4) Inside the VWLAN controller, I created a location with the same subnet and CIDR as the "guest" internet connection and tagged it with VLAN ID 14.
5) I went into the "Roles" section of the VWLAN controller and selected the "guest" role. I changed the location of the guest role to match the location configured in step 4.
6) In the SSID's section of the vwlan controller, I created the Guest SSID and then assigned the vlan 14 "guest" role to it. Don't forget to set your firewall rules.
7) I went into the AP Templates section and assigned the guest SSID to the radios.
8) I applied the templates to the AP's.
I have marked this questions as "assumed answered".
If this is not the case or you have more questions, feel free to respond to this thread.