Modification of Custody: is a trial necessary?

I am the non-custodial mother of a beautiful (almost) 4 year old daughter. There is a long story to this whole thing, so I'll just give you what I think are the important facts. I have been divorced (legally) for one year. We had a child custody bloody dispute. We had to go to an "expert", who found that we were both qualified and loving parents but that if she had to choose a primary parent she would choose the father. This was based mostly on the fact that I was haing an affair and in the transition of moving in with him, and my birth family turned against me. (we are now married). I agreed to every other weekend (Friday evening to Monday morning) Dinner times 7:00 - 9:00, every other holiday and two weeks vacation in the summer.
Here is the problem...I can not pick her up from school at 6:30 (he states it is not within the prescribed time). I now have 1/2 working days on Fridays which would allow me to pick her up at 3:00 on Fridays from his parents home (she's there mon and fri). He told me he will not allow me to do this and that I have to wait until 7:00. On "his" holidays, he works (construction) but gives our daughter to his parents to care for, when I am home and very ready and willing to care for her.
I explain to him that the experts recommendations are guildelines, not"bible" and that there is nore ason why I can not spend time with her if I am blessed with the time to spend.
As I said, I am now re-married and we plan on trying for a child immediately. I would like to file for a change in custody based on change in circumstance and the fact that her father does nothing to "bolster" the mother/daughter relationship as he also agreed to. He also agreed to attend therapy to deal with the negative feelings that he has against me,but has not done that either. Apparently I am the only parent that has to follow the rules.
1) If I file for change in custody...is their a trial involved with witnesses and all?
2) Does anyone have any other suggestions on how to handle this situation?

Thank you very very much