What I did with my double pan is use a piece of tin foil between the gasket on the lid and the lid surround. Mainly from the point of view to keep it airtight but it did also have the added benefit of stopping the tar build up. And you have to have a good, tight seal on that lid.
Learning generally boils down to "Repetition or the avoidance of pain", some people learn by doing, some by watching and some just have to pee on the electric fence.
Whether you think that you can, or that you can't, you are usually right. Henry Ford
I have probably 15 cooks in my mini gravity feed and have used chunks of oak,mesquite,hickory,apple,pecan and pellets and haven't experienced any issues with a tar type build up or gasket issues. Seems like your gasket issue may be a symptom of something else that needs corrected, possibly a moisture issue or something with the type or quality of chunks your using. Not sure just a thought.
Grandma always said "if ya can't be handsome ya better at least be handy"
No I've used both lump and briquettes, I wish I had an answer for your problem. Maybe try a different type charcoal and see if it changes anything in regards to your creosote issue.
Grandma always said "if ya can't be handsome ya better at least be handy"
Same here I put a chunk or two in the ash pan at a time. What temp are you running at and how much smoke are you getting out of the stack? I run mine between 225 and 250 with just a hint of blue smoke coming out of the stack.
Grandma always said "if ya can't be handsome ya better at least be handy"