My account creation experience went very well. Problems started after that.
I tried twice to upload an OpenSCAD template. Upload reported success, but I can’t find the model. The second time I saved the model ID: MOD230212FRW2R.
Sorry, you had a bad experience. I am happy to help and interested in your observations.
When a model is done processing, look in the “OpenSCAD Model Results.” This is under the hamburger icon on the top of the page. It is only in the queue for as long as it is processing, and the system is speedy.
I will check out your wall plate model and let you know what I find.
I took the liberty of recording a video of using the customizer with your existing Thingiverse model. Please feel free to post any additional questions, and if you would like me to walk you through creating a new model on the platform, I am also happy to do that.