It might seem gross to put toilet paper into a special wastebasket rather than into the toilet, but it’s worse when the toilet becomes clogged and starts to smell. One way an RV toilet bowl clogs is due to the toilet paper used, so choose degradable paper or put a bin in the bathroo...
If you can see how the underside compartments are attached to the RV, look for cracks in the plastic that might indicate the compartment was overloaded at one time or another. Also, check for the amount of dirt in the compartment. Is it more than a tiny bit?