I've applied Outland for Costa Rica, so it will be processed in Mexico.
I submitted about 40 photos that spanned out entire relationship, I wrote a description on the back of each. For #9 I wrote an entire page summarizing our relationship. I tried to keep details to a minimum in case they want an interview, wouldn't want to have to memorize everything I wrote. I also was pretty vague in this question about the wedding, reception and honeymoon because they ask specifically about those three in other questions where you need to be more detailed so I thought it would be unnecessary. For our wedding I have the script that the officiate used so I put a copy of that in there. At the reception I made a speech so I put a copy of that as well. For the honeymoon I put the hotel invoice, copies of our passport stamps entering Nicaragua, and the tourist cards they gave us. For proof of my visiting him I have printed off my flight itineraries, given copies of my passport stamps, and I had one boarding pass that I threw in too. We applied for a trv and were denied so I put the denial letter in there to show the reason he didn't visit me in canada. I had probably 40 pages of Skype call history and video chat history to prove our communication while we are apart. And I included the western union receipts that we were able to find to prove that I was sending him financial aid. This was everything I included for the imm5490 or whatever.
For extra information, stuff that they didn't specifically ask for I have letters from my grandparents and my mom showing support of Gerald and our relationship and my decision to bring him to canada. My grandparents letters each offered him employment and my moms letter offered us lodging. Gerald and I have a 13 year age difference, so anticipating that this might cause extra scepticism, I wrote a letter directly addressing that issue.
You should also know that I am the sponsor, the Canadian, and my husband only ever touched one of the forms only to sign it. I have heard that this is actually a pretty common thing, and I don't think that it will affect our application. Lol.
Let me know if anyone has any questions.