Hi Tom,
Can you check below as comments please:
1, Use static IP address rather than with DHCP setting.
2, Make sure the gateway ip address(setting with the configuration tool) is the same as your wireless router’s. If it works under ad-hoc mode, it must be the same as the ip address(server).
3, If you are in North America, you probably need disable one or two WiFi channels or select your location as ‘Europe’, more details of the WiFi channel difference can be found from:
https://en.wikipedia.org/wiki/List_of_WLAN_channels
Beyond above settings you should also confirm that the power supply could drive enough current.
Keep us updated please.