I usually save my file as a Flexi file.
Then I open it in another window and draw a box around it leaving a comfortable margin, and click on the X on the end of the color chart to make it clear.
Then I select all and convert it to paths, and reduce it proportionally to around five inches tall.
At that point I can export it as a jpg at 300 dpi without any compression. These seem to be openning clearly .