1: Engaged users.
This represents the sum of all likes and comments for all the posts in the selected period.
As you thought, this is the average comments and likes a post gets.
As for the decimals - that comes from taking the average.
Ex: Post1 : 5 engagement, Post2 : 4 engagement -> 4.5 Average engagement/post
4: Time to post.
This shows the hours the IG profile posts the most. You can get a sense of when that profile is most active.
5: Daily top filters.
This seems a bit off - we might have a bug there. It should be the same as the Top Filters section of the dashboard and show the most used filters by that respective profile for that period. (normal being no filter)
6: Top Hashtags.
The top 10 hashtags the user used. They are the most used ones as we couldn’t reach consensus on determining what are the best performing ones.
(I will update this answer with the missing info for number 3)