Please check on the bottom of the lantern for an area that you can twist to open. If this process fails, please call manufacturer for copy of product manual. Thank you.
Please understand that you are talking to regular people who offer advice on FixYa forum, not to Coleman.
You could check with your local historical societies or museums.
Read page 3 of the manual.
The red light is on when charging, it does not change colour but goes off when not charging. It will take up to 18 hours to charge for 9 hours of use on low.
12V Lead acid battery should be kept charged all the time, even when in storage.
I found that bashing it with a hammer numerous times helps to alleviate some of the frustration plus what does it hurt? Not like the damn thing was working anyway