A lot of people followed and helped my install last year with my nc30. Heat my house like a champ. But after installing my block off plate inrealised I did not set any screws at the stove collar, 45 degree angle , or where my 25 ft liner meets my angle. There was a good weight pushing down on these parts making a snug fit. Is there anything to worry about or do you think it wil be fine ? Thanks again