To drag and drop items onto a task
- If the TimeLiner window is not already open, click Home tab  Tools panel Tools panel TimeLiner TimeLiner  Tasks tab. Tasks tab.
- Select the desired item or items in the Scene View, or in the Selection Tree. Tip: Holding down the spacebar when using the Select tool switches the selection tool to the Select Box tool, enabling you to make a 'group' selection. When you release the space bar the selection tool reverts to the Select tool, retaining any selections that have been made.  
- Drag and drop the selected items onto the required task in the TimeLiner  Tasks tab. Any existing attachments will be overwritten with the dragged items. Tip: If you hold down the Control key when dropping items they will be appended to the current attachment.  Note: Items can be dragged onto a task in the Tasks area or in the Gantt chart.