Hi Shivaprasad,
Please find my comments below.
1) If you are uploading the leads through excel you have to maintain those values in excel. If not you can hard code or by reading the sales area data from the transaction using FM CRM_ORDER_READ.
Pass the data to it_orgman parameter of fm crm_order_maintain.
2) Yes.. the format 20150415220000 is in time stamp format YYYYMMDDHHMMSS. For that filed give right data element in the structure. For the field name and data elements do F2 in start date and end date fields from webui (or) F1 for the date fields in transaction CRMD_ORDER.
You have to pass the data in similar format of the fields and pass to parameter it_appointment of fm crm_order_maintain.
Sample code:
....
timestamp_from TYPE crmt_date_timestamp_from
timestamp_to TYPE crmt_date_timestamp_to
....
Regards,
Varma