This is the second post dealing with the target button for the validation exercise under "Designing a case life cycle" subsection "Validating case data". Instruction #5 tells you to open a Create Validate form but the screenshot shows that hovering over the button only displays the words "Open Service Level Agreement". The button itself does nothing. I'd also like to know how to see my posts after submission. That answer would have to be included in a separate correspondence please.
Ignore the tooltip that shows up. It should open the validation rule, or open the Create form to the validation rule. If it does not, check if you have enabled pop-up in your browser. You may also want to try using another browser. This is a browser issue.