Although the letter from Chris to RJ shows Chris Merrill's name spelled with two "L's", the credits show his name spelled as Elder Merril, with just one "L".
When Elder Merill enters the apartment to meet Elder Smith for the first time, the bathroom light is off. As the two get acquainted, the light is on at times, then off again.
The Mormon figures he has in his suitcase then leaves them in the room when he leaves. But in Testament of Love the Mormon figures are by RJ's computer.
When Elder Merrill was meeting strangers on the sidewalk in the commercial district of town, he said to Trina, "I'm with the Jesus Christ of Latter-day Saints." He inadvertently omitted the words "Church of."
Neither of the envelops from the letters RJ receives from his girlfriend Elise and later from Chris have postmarks or stamp cancellations.
When Elder Smith is having a conversation with his father at the end of the movie, close-ups of his father reveal that his left ear has a piercing hole in the lobe, something that would be very unlikely on a Mormon man. Comparisons with the right ear verify that it is a piercing hole.
When Elder Smith meets the stake president in his office, the voice actor (Barrie Wild) ends his prayer by pronouncing "amen" with a "short a" (i.e., ah-men). Elder Smith then says "amen" with a "long a" (ay-men), which is the pronunciation used by the LDS faithful.