thank you for your great overall product & support. I'm delighted to have the ability to decide the SW which runs on my devices.
Below my setup - which I've failed to have working. I'd be grateful for guidance.
Sumary:
Modem TWG870UG remains in gateway mode since it cannot do bridge mode. WR1043N set up as gateway: no Internet access.
My purpose:
I'd like my 2 teenager kids to sleep at night.
My context:
Living in Switzerland, internet provider "UPC Cablecom", cable modem is Thomson TWG870UG, which does cable modem + VOIP + TV + Internet Gateway + Wireless access point.
Cablecom's version of TWG870UG does not offer the switch to "Bridge" mode (I've asked Cablecom support).
TWG870UG working fine, Internet access + wifi.
TWG870UG HW version 1.1, SW version STBA.01.75.
TWG870UG does not seem to offer a simple "setup sumary" extract, please inform if I should push some specific settings.
On the TWG870UG I've set "DMZ Host (Exposed Host)" to 192.168.0.10 hoping it would help, although I've not observed a change.
TWG870UG does not offer usable parental control, therefore I have installed Gargoyle 1.9.X (Built 20160722-0837 git@9156807) on my TP-Link TL-WR1043N/ND v3.
Configuration of the WR1043N went smoothly

TWG870UG remains working as a gateway (no choice), plan is to turn its Wifi down & ethernet output unused but the one which feeds the "WAN" input of the Gargoyle gateway. Below the config of the WR1043N.
My issue:
"No internet access" reported on my Windows PC when pluged into the Gargoly gateway (ethernet).
No access to the modem admin pages 192.168.0.1 from above PC. Ping fails. Current devices on 192.168.0.x LAN (on the TWG870UG) are not visible.
Note I do not know whether the problem lies in the Thomson modem, the Gargoyle gateway, or my setting (one gateway behind another gateway - I do not see why this should not work but I have little experience here).
Thank you in advance for guidance,
Danhilu.
Gargoyle Status
Device Name:Gargoyle
Gargoyle Version:1.9.X (Built 20160722-0837 git@9156807)
Model:TP-Link TL-WR1043N/ND v3
Device Configuration:Gateway
Memory Usage:16.7MB / 59.7MB (28%)
Connections:210/4096
CPU Load Averages:0.33 / 0.24 / 0.10 (1/5/15 minutes)
Uptime:0 days, 0 hours, 2 minutes
Current Date & Time:09/25/16 5:46 AM CEST
WAN IP Address:192.168.0.10
WAN Netmask:255.255.255.0
WAN MAC Address:F4:F2:6D:52:AE:4F
WAN Gateway IP:192.168.0.1
WAN DNS Server(s):8.8.4.4
8.8.8.8
LAN IP Address:192.168.1.1
LAN Netmask:255.255.255.0
LAN MAC Address:F4:F2:6D:52:AE:4E
Port Status
LAN1 -
LAN2 -
LAN3 -
LAN4 1Gbps
Wireless Mode:Disabled
QoS Upload:Disabled
QoS Download:Disabled