Not sure if this helps about the custody thing but someone asked this law question:
If Sandra Bullock Divorces Jesse James, What Rights or Privileges Will She Have With Respect to His Young Daughter Sunny, Whom She Has Helped Raise?
It really is a good read, non tabloid. From what they say (my take from it) Jesse has full custody of Sunny, and that Sandra helped him but doesn't lawfully have custody because Sunny's Bio mom never reliquished her rights to Sunny, and she would have had to in order for Sandra to have any parental rights to her, I do know the kids were with her while he was in rehab and that because he had full custody, while he was in there there was mention in one story that she had a temp custody order which is standard as a non custodial parent, it would allow her to seek medical attention should Sunny need it, or sign for something, etc.
Sounds to me like Sandra and Jessie talked which is good, because it will help to work things out, as for him being apart of the Baby's life after the divorce. I can see that he was there from the start maybe he bonded with the baby as she did with his kids. I know Jessie has stated that he has accepted (since being in rehab) what he did was wrong and it hurt his family and that he is to blame for it all. But from the news reports on them, the agreement to sell the house, split the stuff in it, etc plus the kids, they had to have discussed this at some point. It has been shown that they can hide things from the public eye (example Baby).
So I wouldn't be surprised if somewhere down the road Sandra and Jessie continue to work out the problems (while they may never get back together) so that they can both find the closure they need and still keep the stability their lives need as individuals and as a family they once were.
As to his selling the Magazine that could be part of the split if Sandra had any monatary interest put into it. Or it could be that he is scaling down, lost interest in the magazine, or maybe its not making the money it once did and he wants out before it hits bottom. From what I understand its not because he lacks money (unless I missed something or someone reports it later) because it was once said that Jesse married Sandra for her money, but it turned out that it wasn't true, he had plenty of money from all his business's, etc. to the point he was (some say) in, around, at or above Sandra's pay bracket if you will. So basically the "he is a gold-digger" thought flew out the window.
I honestly hope that they do work it out (not the get back together, if they do thats on them) because they have so much invested right now step back take the time needed and maybe work out a friendship, they will probably be seeing each other alot especially if she is allowed (and we know she will be as reported) visitation with the kids, him with the baby, seeing each other around in general. It would be better on both of them and the children involved. IMO.