The yellow diamond at rule running means that no new posts were imported at the rule running (but also no errors were encountered). If an error was encountered, a red X shows.
The yellow diamond appears usually in two cases:
1) if all posts were already imported from for the specific rule. Posts will be imported automatically, at the schedule you set, if new content is available from the API, which is not already posted to your blog. In this case, you should wait a couple of hours or 1-2 days at max, to see if posts are getting imported automatically to your blog.
2) if no post is getting imported, you should check the ‘Posting Restrictions’ settings, in plugin’s ‘Main Settings’. These can prevent posts from getting imported. Please check the ‘Minimum Title Word Count’, Maximum Title Word Count’ , Minimum Content Word Count’ , Maximum Content Word Count’, ‘Banned Words List’, ‘Required Words List’, ‘Skip Posts That Do Not Have Images’ or ‘Skip Posts Older Than a Selected Date’ settings fields in ‘Main Settings’ – these may prevent posts from getting imported. Please clear them, save settings and rerun importing, to check if these were the ones preventing proper post importing.