Hi Otto,
Sorry about the inconvenience caused.
We would like to inform you that , our latest version of Essential Studio is 13.1.0.21 , and we could not able to reproduce the issue reported by you in this version while rendering Gantt . Can you please share us the detail of the Essential Studio version you are using ? . This is will be helpful for us to provide the solution even better .
Also we have prepared a sample for rendering Gantt with the latest version of Essential studio. Please find the sample in the below location ,
Sample: http://www.syncfusion.com/downloads/support/forum/118964/Vol1_15Localization1398751937.zip
If you still facing problem to render the Gantt Control, Please revert us by modifying the sample according to your requirement along with the replication procedure to help you better.
regards,
Mahalakshmi K.