What do you mean exactly? Do you want to set property value of thing from external application? Could you please give detail information about your question?
Sorry for my lack of detail.
I'm just getting started with Studio, and I was able to publish an experience with one of my 3d models and tie a 3d gauge to show dynamically the sample data from your sample called FAN -RPM value.
Next I would like to call an api on the web where I can access some of my own live sensor data and tie it to a 3d gauge in this model in a similar way.
Should this be possible?
You can get data of your property via api for your custom web application.
I hope, these documentation will help you;
TW Rest Api Cheat Sheet: ThingWorx REST API Cheat Sheet