You get an error when installing your template
Wait and try to install the template again in a few minutes. If the template fails again, see what object it refers to in the error message and see if you can locate it and delete it, for example, a step in a workflow or a menu item. Then try to install the template again. If the template still fails to install, please raise a support request using your account on this support site.
You've installed your template and added your content, but nothing shows in the blocks on the page
Edit the block on the page and check the filters. If the filter looks right, try removing the value and re-adding the value again. Save your changes and check to see if the content now appears.