Understanding analyses

I need help reading the analyses provided in the Tactics Trainer. I pasted one in below as an example. There are many symbols here I don't understand; is there documentation anywhere on how to read them?

Not exactly sure what the numbers 12: and $18 mean, but Mat02 means mate in 2, and numbers such as +6.04 and +6.15 means that white has an advantage worth about a rook plus a pawn (5+1 points). The move sequences in parantheses are alternative lines, each denoted by its point value. Mat02 is, of course, the best alternative.

Now that I look at it again, that "12:" could have something to do with the depth of analysis, i.e. how many moves into the alternate lines the analysis go.

$18 is how much the computer suggests you bet on the game, if you are playing white, to get a good return.

Really? So it's an assessment of your odds of winning from that position?

I'm thinking "not really".

I have six chess.com analysis PGN files on my drive, and half of them have $18 after each analyzed line and the other half have $19. If I had to guess, I'd say it's the number of the processor used in making the analysis, although if they have at least twenty of them, I can't figure out why only two of them would have done all of mine.