My issue is how to test it
There are two namespaces related to IAP function: Windows.Services.Store
and Windows.ApplicationModel.Store
.
If use the Windows.ApplicationModel.Store
namespace, these apps can use the CurrentAppSimulator class to simulate license info during testing. See In-app purchases and trials using the Windows.ApplicationModel.Store namespace
While the Windows.Services.Store
namespace doesn't have a class to do so.
Please see the testing guidance
The Windows.Services.Store
namespace does not provide a class that you can use to simulate license info during testing. Instead, you must publish an app to the Store and download that app to your development device to use its license for testing. This is a different experience from apps that use the Windows.ApplicationModel.Store namespace, as these apps can use the CurrentAppSimulator class to simulate license info during testing
(Update 10/21/2016)
I'm not clear about your development device sentence though. The app is developed on a Windows 8.1 device and is uploaded via a Chrome browser
That sentence is quoted from this document
It means we need to convert the Win32 application to Converted UWP app and upload to the Store first, even though we have not implemented the IAP function.
Is there a way to manually associate an app with a Windows desktop?
Sure, please see Create your app by reserving a name
Here is a screenshot of App identity of a uwp app on the Windows Dev Center
Note, please fill this form if you need to upload a Converted UWP app: LINK
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