Question: Wouldn't Earth's gravity cause Gardner's feet and leg to ache, given that he is from Mars, a planet with much lower gravity, and has lived there his entire life?
Answer: Any answer would be speculation at best, although it does seem likely that being on Earth would cause various pains. But it also depends on his conditioning while on Mars (for example, soldiers in the military often train with heavy packs on). The reason astronauts experience pain upon return to Earth after long stints in space is mainly due to muscle atrophy, similar to someone being bed-ridden for months. Additionally, being weightless in space with 0-g's (not zero gravity), their spine elongates and then back on Earth, it compresses back to normal, which can be painful. Gardner may not experience pain since his muscles aren't atrophied, and he may not experience spinal compression.
Question: Why would they make Anne Australian? Her nationality isn't even mentioned, so why would they let Abbie Cornish use her natural accent? What purpose does it serve? It seems like an incredibly random choice. Abbie Cornish has used an American accent in most of her roles, so of all the ones to use her natural accent, why would she use it in the one where it makes the least sense? Why would an Australian go to a small Ozarks Missouri town? I assume she stayed there because she met Bill and fell in love with him, but why would she have gone there in the first place, before she met Bill?
Answer: Since the movie doesn't tell us how she and Bill met, any answer about how and why she was there would be mere speculation. Letting an actress speak in her native accent is not exactly "random"; random would be if she was an American and the writer/director decided to make her character Australian. However, the situation of an Australian marrying someone from, and then living in, a small Missouri town is not as outlandish or nonsensical as one might think; I used to date someone from a tiny town in Kansas, whose mother was an upper-class British woman who happened to meet and marry someone from that town.
Question: The producer in the restaurant scene, played by Judd Apatow, who rudely tells Tommy that he's never going to make it big - was he a real person? If so, did he ever see "The Room" and bump into Tommy since?
Answer: A lot of movies will put a title card at the end of the film before the credits. It's usually to cap off the movie so that it's the last thing you see or think about when you leave (especially back in the day when you didn't sit around to watch for an extra scene). They want it to be redundant so you don't forget (repetition is the key to learning). Most movies (if not all) also have the movie's name at the very end of all the credits too. But I assume for copyright or other legal reasons, the same way a book publisher might print the book's title on every page of the book.
Bishop73