From my experience i can say that not only new users but also old user often find it difficult to change their LogIn password. but its really so easy to do this. . .
Do the following steps to change password.
First log out from your account. Click here
peperonity.com click Login. A new page will appear on the screen. Take a look on the bottom. There you find 'change password' option. Click 'change password' and it will lead you in a new page where you can see four text box. Then fill those 4 box with proper information(ie. your user name, old password, new password, confirm/repeat new password). . . Now click the command button(it can be named as OK/CONTINUE/SAVE).
if you successfully able to follow all these steps and then from the next time you are allowed to login with your new password.
Cheers!