1. She is entitled to maintenance if she is does not earn anything of her own to maintain herself and such maintenance amount is fixed by the Court which is normally in between 1/5th to 1/3rd of husband's net monthly earnings,
2. If she refuses to sign MCD petition, file a divorce petition on the ground of cruelty,
3. Collect copy of her ITR filed before the I.Tax department and/or other papers to prove her actual income. If she is capable of maintaining herself, she is not entitled to any maintenance from you,
4. No. That amount you have paid before filing the divorce suit. However, you can draw the attention of the Court to this fact and also that she is deriving income more than that of yours from her busyness funded by you.