PCBWay has a new feature full Online Gerber Viewer.
https://www.pcbway.com/project/OnlineGerberViewer
This reads all your Gerber files and allows you to double check your board layout, substrate, copper layers, mask and silk screens all in your browser!
The boards came out great and they shipped really fast. Their pricing is also a great value. I will be using their service for future product runs on Tindie
I just encountered this issue, however the solution is displayed on this website, which helped me. A helpful link is provided here if you would want to learn more. https://coderscage.com/