Hello! I understand your new puzzles in the Vita Jigsaw app are not loading properly, and the existing ones only get about 75% installed before stopping. Let's work through this together.

First, to better assist you:
- Are you connected via Wi-Fi or mobile data?
- Have you noticed any internet connectivity issues?
- Did this problem start recently after an update or any changes on your system?

Meanwhile, here are some step-by-step suggestions to try:

1. Restart Your Device
A simple restart can clear temporary glitches affecting installation.

2. Check Storage Space
Make sure your Windows device has enough free space to download and install the puzzles completely.

3. Verify Internet Connection
Since puzzles need to download content, a stable and reasonably fast connection is important. Consider switching between Wi-Fi and wired Ethernet to check if that helps.

4. Close and Reopen the App
Fully close the Vita Jigsaw app and reopen it to reset its state.

5. Run as Administrator
On Windows 10, sometimes running the app with administrator privileges can resolve permission-related issues. Right-click the app icon and select "Run as administrator."

6. Check for App Updates
Ensure you have the latest version of Vita Jigsaw installed. Developers often fix bugs in updates.

7. Clear App Cache/Data (if applicable on Windows WebKit app)
If possible, clear the app cache to remove corrupted temporary files that may hinder downloads.

If after these steps puzzles still won't load fully, there might be a deeper issue at play such as server communication errors or app-specific bugs. In that case, could you please confirm if you see any error messages or if the app shows any codes during the failed download attempts? Also, double-check that your Windows OS version 10.0 is fully updated.

If needed, I can help you escalate the issue to our support team for a closer look.

Please try these steps and let me know what happens. Are you satisfied with this approach so far?