Connected To Wifi But "Not connected to the internet"

I downloaded and installed the AstroBox-rpi-0_11_24-20180322 build. I updated /etc/network/interfaces to have my network information per the can I configure the Raspberry Pi network myself page and it’s working fine in that regard, in that it connects to my network. During Astroprint setup, it wouldn’t let me sign in to my Astroprint cloud account and, after skipping that, the dashboard claims “not connected to the internet”. Additionally, nothing is shown in the Internet Settings page.

From the CLI, I was able to perform the wget https://api.astroprint.com/check and then checked the response with cat check, which showed a successful response.

This is on a Raspberry Pi 3 B+, with v0.11(24), using the built-in wifi after manually configuring network settings (per the above linked wiki).

This appears to work correctly with the same steps and same source image applied to a Raspberry Pi 3 (model B, not the new B+).

Have you read/done this? https://astroprint.zendesk.com/hc/en-us/articles/207866186-Can-I-configure-the-Raspberry-Pi-network-myself-

I did, hence why I referenced and linked to that very page in the question. That approach is also why the 3B+ was able to connect to my network over wifi at all (just using the built-in wifi, after initial connect over ethernet, no dongle). Strangely enough, I don’t think that is my current root problem.

At some point, my controller board appears to have become bricked. I am currently awaiting an ISP I ordered to arrive, expected tomorrow. Once my board is working correctly again, I will ascertain whether a 3 or 3B+ (since I have both available) works correctly with Astroprint. As it stands, I suspect things should improve over the weekend and I will update the status of this afterwards. Thanks.