Yes - I assume that the Unix epoch dates are simply due to null values in this case.

And the 10000 numbers represent two decimal places (i.e., 100.00).

That comment body was truncated by me in the interest of brevity (and I added the "...").

depth is determined by parent/child ancestry. The first level comments of a post are depth 1 (i.e., consider the post to be depth 0). The replies of those comments are depth 2, and their replies are depth 3, etc.

When rendering, I probably would use nested <ul> so that I wouldn't necessarily have to worry about the depth, though. I only mention it in case each node was rendered individually and you had to figure out the indent level.

Thanks for reading!