Well, we are all new to this, so maybe FMI will clarify but hey.. Ill give it a shot based on my testing so far.
1. Yes, I tried my own solution which has a large number of internal relationships and and also 4 related files, this appears to be working very well locally and hosted.
2. I think you may have to embed the photos for it to work, maybe there is another way but I doubt it.
Embedded images display fine.
1. Yes, this will work.
2. No, this won't work if the images are linked using a container field. However, FM Go supports the web viewer field, so I would use the web viewer as a workaround for displaying those external images.
Thanks for posting.
Here are some links to Knowledge Base Articles that you may find useful:
FileMaker Go behavioral differences for specific features such as text editing, sorting, etc:
FileMaker Go behavioral differences for calculations and scripts:
Hope this helps a bit.