Custom Opencart Development

We have a partially developed Opencart website that needs further development and customization.

Key Requirements:
- Development & Customization: I seek a skilled professional to enhance and customize my Opencart website.
- Design: The project will involve customized theme design and creating a more user-friendly navigation system.
- Bug Fixing: Some bugs have been identified in the partial development that needs to be rectified.

Skills and Experience:
- Proven experience in Opencart development
- Strong understanding of PHP, MySQL and OpenCart's MVC architecture
- Experiences with payment gateway integration
- Ability to design customized themes and improve user experience
- Attention to detail and ability to identify and fix bugs efficiently.

Please provide examples of your previous work and explain your experience with Opencart in your proposal.