Laptop, Win 10, I enter correct password and press enter and BSim launches.
Enter incorrect password and press enter and I get the red fail screen but the password box and avatar remain on the screen so I can correct it.
Your avatar looks black and white on your picture. Is it supposed to be black and white, if not, I would uninstall and reload from the BKool website.
Get rid of any saved passwords for BSim in your browser as well.
In Google got to Settings>Advanced Settings>Passwords and Forms>Manage Passwords
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