About the WhatsApp question, its not the quantity that maters, its the quality. I think that 60 is more than enough ( I submitted less). My conversations were in Ukrainian and I didn't translate them at all. As far as I know, the evidence is looked at when your case reached the embassy. Someone there must know french. That's why I didn't translate my conversations because they will be looked at by an officer in the Ukrainian embassy, and the offers there obviously know Ukrainian ! You can put as many photos on one word document as you want. But I would suggest to put them in a way where everything can be easily seen. I made screenshots from my iPhone, made the word page horizontal, and put three pictures with captions on the bottom. There were some pictures that took up a page, but mostly I either had two or three pictures per page.
Make sure you submit evidence that you two have met 2 years prior to submitting I-129, include two signed and dated letters of intent to marry, 2 passport photos ( with names on back), and check . *These are crucial* !
