You can easily create a new password for your existing Demola account. Follow the following steps for that:
When you are asked to login, click in "Forgot your password":
Fill your Demola account e-mail address and click in "Reset my password":
You will receive an e-mail message with a verification code required to reset your password. Do not share this code with anyone! Check your e-mail inbox and possibly spam/junk folder for the message. It will be sent from "no-reply@demola.net" and it looks like the following:
Go back to the browser, fill the verification code received in the e-mail message into the Code field, and create a new password for your account (your password should be longer than 10 characters). Then click in "Change Password":
Done! You are now able to login with your new password.