All the tools (line, zigzag etc.) have default properties that are set by double clicking on them. Enjoy!
I meant double click on "them" - the tools, which together constitute the toolbox, not the drawn item. When you want to draw a zigzag line you go to the zigzag line tool.
What pops up will be the properties that have a default nature.
Line width is not one of them. Line width is set in the universal default selector below the shape sheets display - along with the choices for start and end arrow type, line type, and line and shape color and background. You have 5 preset line width selections. Beyond that you have set the properties of the individual lines.
You can select multiple items, and then double click one and get properties for all of them in one properties dialog and all will be changed wholesale. You can select by dragging a box around them, or by picking
If you apply, not close, the dialog you can then double click on another item or selection of items and the dialog will change so you can edit these properties.
Here is an exact procedure for example:
Pick the line tool, and draw a line. Double click on it and change a property. Click Apply. Now draw some other things like a bezieregion and an image. Select all three by dragging a box, and double click one of them while they all have their grips showing. The properties dialog will change to reflect the properties of all the items selected.