Trying to clear a project's tasks leads to an exception. The reason is the destructor of TTMSFNCGanttTask. It should first call FOwnerProject.RemoveDependentTaks(Self) and then free the task's members.
Thank you for letting us know, although we weren't able to reproduce this issue, we made the changes as advised.
Ths will be fixed in the next release of the TMS FNC Gantt Chart.