I've been trying for a week now to configure my 2860n+ and so far have completely failed to get it working properly. I'm beginning to think this router is seriously flawed. All I’m trying to do is block gambling sites (http and https) and other inappropriate content.
What I am trying to do is relatively simple, or so I thought. Here’s what I’ve done so far.

I have bound all devices using MAC IP Binding.
DHCP Address leases range 192.168.1.100 - 200

IP Ranges defined
Servers and media devices: 192.168.1.10 - 49
My Devices: 192.168.1.50 - 59
Other Devices: 192.168.1.60 - 69
Kids Devices: 192.168.1.70 - 79

Web Content Filters (paid for subscription)
BlockAll - All groups are blocked
Servers - Pass All
MyDevices - Pass All
OtherDevices - Blocking news and
KidsDevices - Blocking news and

DNS Filter
Enable: True
Service: WCF-4 OtherDevices

Firewall Filters in Set 2 (Default Data Filter)
xNetBios -> DNS
Block All
IP Source: Any
Action: Block if no further match
Web Content Filter: BlockAll
Servers
IP Source: 192.168.1.10~192.168.1.49
Action: Pass if no further match
Web Content Filter: None
My Devices
IP Source: 192.168.1.50~192.168.1.59
Action: Pass if no further match
Web Content Filter: None
Other Devices
IP Source: 192.168.1.60~192.168.1.69
Action: Pass if no further match
Web Content Filter: OtherDevices
Kids Devices
IP Source: 192.168.1.70~192.168.1.79
Action: Pass if no further match
Web Content Filter: KidsDevices

Test Results

To test I used 2 sites http://www.bbc.co.uk and https://www.bingogodz.com

From Servers Group
bbc - blocked - wrong!
bingogodz - failed to block - why?

From MyDevices
bbc - blocked - wrong!
bingogodz - failed to block - why?

From OtherDevices
bbc - blocked but now message as to why
bingogodz - not blocked - should have been blocked


I can only assume the Draytek is not u pto the job

Try your devices and servers action to be "Pass Immediately"

Leave the XNetbios Rule default and start your customs Rules under that.

I might be wrong but the Drayteks are logic engines that work top down and doesn't match rules its already passed above.

Have you associate and WCF to the Default Rule under the firewall general setup?