To automatically move to the next cell when a specific condition is met, you can subscribe to the ValueChanged event of RadGridView and add your own logic. You can find a sample implementation in the attached project. Feel free to refer to it or edit it and do not hesitate to write again if you have any additional questions.
I hope this information helps.
Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.