First, you need to create an account to use the bug tracker. You can do it here: http://forge.prestashop.com/secure/Signup!default.jspa
Fill all fields and validate your account.
Once your account is validated, click here to log in: http://forge.prestashop.com/secure.
You can now create your first issue:
- Click on "Create Issue",
- Choose the project: PrestaShop version 1.4 or 1.5, Prestashop Native Modules & Themes,
- Choose the issue type: "bug" or "improvement",
On the next screen, fill all information to create your issue.