Thank you for the details.
If the java file is relatively large , you will not see the red box on the right aligned to the line of the error. If you click on it, it will take you to the error. This is how it works with Eclipse 3.7 , which is the base version for MyEclipse
Attached is the screenshot taken from Eclipse 3.7 for your reference.
Let us know if you have any other issues.