I had an Osburn 2000 installed and he had a horrible time getting the liner and stove connected. I had the chimmney sweep to check it and he took a picture heto where it shows a small opening where it does not connect. That is just on one side that he could get a picture. Most of time there is a good draft but at times you can not leave the door open because of smoke. Should I be concerned about this issue or is all well? Thanks