In the latest version of the application, the "Gantt Project" icon appears only above the Tasks list. Unfortunately, the software doesn't allow you to remove it and I suggest you export the project to PNG or JPEG and then to edit the file using a photo editor. You can export it from the Project > Export menu:
Also, if you want, you can print only the chart without the Tasks list. To do this you need to press the button between the chart and the tasks:
If you have issues, I suggest you contact the support team using the information from the official web page.