I have run into a snag using LiveCycle for form development. Whenever I select any of the black bars that form the structure of the form, these gray lines appear out of nowhere. I know I did not intentionally activate anything. At first I thought they were guide to help the user see smaller objects but that was not the case because when I went to print the form those gray lines were clearly visible on the printout. I do not use Java to develop these forms.
I went through and set my drawing aids to match what you posted and the gray lines are still appearing. I've scoured the internet and many forums but I have not seen this issue reported anywhere else. The odd thing is that it only started happening when I began using the ES4. When I used ES2 this was never an issue.
I am having the exact same problem. I've noticed that when I save the document and come back to it, more lines appear. They won't allow you to select them to delete them either. I can't figure out how to get rid of them. When I try to use ES3, they still show up.