Windows Flash Tool with Dynamic DLL

I need a lightweight Windows-only desktop application that can flash our proprietary, Windows-compatible device in a secure, modular way.
The workflow is straightforward:

1. At launch the app asks the user for an alphanumeric Token, grabs the machine’s HWID, and posts both to my backend endpoint POST /api/v1/auth/verify. Until the server responds “OK”, every flashing-related control must stay disabled.

2. Once authenticated, the user presses “Flash”. The app silently pulls the latest firmware package from my server and, at the same moment, loads the separate flashing engine DLL straight into memory (the DLL is not compiled into the main executable). After a successful in-memory load, the engine takes over and pushes the firmware to the device over USB.

3. A clear progress bar and status messages (“verifying token”, “downloading firmware”, “loading engine”, “flashing complete”, etc.) keep the user informed throughout the process.

Deliverables (acceptance criteria)
• One Windows 10+ executable that meets the flow above
• External DLL loaded dynamically at runtime, not shipped statically inside the exe
• Source code with concise build instructions so I can update the DLL or API URL later
• Brief README outlining token/HWID collection, the verify call, and where the firmware URL is defined

Successful delivery is a single-click flasher that cleanly separates authentication, firmware download, and a hot-swappable flashing engine DLL.