Quick Steps
Follow the wizard from menu New > Example > DVT > DVT Custom Dialog and place the customdialog.swtxml file in your DVT project.
The SWT/XML Editor and the SWT/XML Preview View will open. In the editor (bottom side) switch to the Source tab instead of the Design tab.
Change the title of the dialog by editing the id attribute of the topmost (first) Composite element
Craft the dialog to the desired look by using the provided examples, autocomplete (Ctrl+Space) and the SWT/XML Preview View
Create a Run Configuration and specify as command echo ${dvt_dialog_prompt:customdialog.swtxml} and run it to see and verify the output produced by the newly created dialog
When you are content with the output, replace the command with your_script.sh ${dvt_dialog_prompt:customdialog.swtxml}
Note
Please be aware that when using {dvt_dialog_prompt:non-blocking} you should have the Launch in background option (on the Common tab) unset.