In order to master your Mac, you will need to enable Remote Management:

1. Open Settings
2. Select Sharing
3. Enable Remote Management

Your IP address will be listed on the right and under Remote Management: On.

To secure access to your computer, you can optionally add a password:

1. Select Computer Settings
2. Enable VNC viewers may control screen with password:
3. And enter a password
4. Click OK to save changes

Master Me currently restores the purchase of any accessories at start-up from the App Store.  The request for your iTunes Password is from the App Store.

For now, you can click Cancel to skip this step.  In the next release, the application will no longer try to restore purchases at start-up.