Gantt chart solution for Zoho CRM?

Gantt chart solution for Zoho CRM?

Hi
We manage events. We have Zoho CRM that holds details about our customers and events. But we need a solution where we can collaborate with customers on the events; setting times, tasks etc

We're thinking a gannt interface is probably the way to go. We thought Zoho Projects might be a solution, however this wont allow customers to add/edit the timeline?

Does anyone know of a gaant chart or event timescale solution that integrates with Zoho CRM?

Thanks