Occasionally, the sent email is missing line breaks that are present in the compose window. This is more likely to happen when text is pasted into the email or when lines are deleted/inserted using backspace/delete + enter. Using latest version: 5.0.18661.0 
Hello,
could you send me one or two of those emails exported to .eml (right click on them - save as…) as attachments to [email protected] together with this topic’s url?
We will look at them and try to find out what and if there is anything wrong with formatting.
regards
Jan