After you have defined your material and support properties with the Define Materials and Define Support options, then you must assign these properties using the Assign Properties option in the toolbar or the Properties menu.
If your model only uses a single material type, or a single support type, then you do not necessarily need to assign properties, as long as you have defined the properties using the first tab in the Define Materials or Define Support dialogs. See below for details.
Tension Crack Properties do NOT need to be assigned. Since only one Tension Crack can be defined for a given model, the Tension Crack Properties (in the Define Tension Crack Properties dialog) are automatically assigned.
Default Property Assignment
When you create a Slide model, Default Properties are initially in effect for all material zones and support (if present) of your model.
The Default Properties are the properties underneath the first "tab" of the Define Materials and Define Support dialogs. The Default Properties are in effect until you use the Assign Properties option to assign other properties.
The advantage of having a default property assignment, is that if you are only working with one type of a given entity (i.e. your model only contains one material, or one support type), then you can Define properties without having to Assign them, as long as you define properties using the first tab of the Define Materials or Define Support dialogs. Even if your model contains multiple materials or support types, the default property assignment is useful, since it is only necessary to assign materials or support types which are defined AFTER the first tab in the Define dialogs.
Assign Properties Dialog
The Assign Properties dialog works a little differently than most other dialogs in Slide. It is known as a "roll-up" dialog, and can be left up on the screen while performing other tasks. The "arrow" button in the upper right corner can be used to "roll-up" or "roll-down" the dialog, to minimize/maximize it without closing it. The dialog can also be minimized / maximized by double-clicking on the title bar of the dialog. The X button will close the dialog.