The best way to add data on the edit page is have all the data you want on the map in a spreadsheet.  If you only have new data on the spreadsheet do the following:

1. Copy data from the form into excel
2.  Append new data to old data into excel file (in the same sheet)
3.  copy/paste or drag/drop the excel file with the combined data into the form.

Example:

If the map contains the following data (it can be copied from the main EasyMapMaker form or may be present in the updated excel file):

Table 1: Existing data
Location number	Address	City	State
1	3611 N Main	Houston	TX
2	5505 LOCKWOOD	Houston	TX
3	1415 E ILLINOIS	Dallas	TX

The data you want to add contains the following 2 entries

Table 2: Data to add
Location number	Address	City	State
4	7401 SAMUELL BLVD	Dallas	TX
5	1209 BARTON SPRINGS	Houston	Austin

All 5 entries should be copied and pasted (or dragged/dropped) into the form on the edit page replacing the existing data.

Table 3: All data for the map (from updated excel file)
Location number	Address	City	State
1	3611 N Main	Houston	TX
2	5505 LOCKWOOD	Houston	TX
3	1415 E ILLINOIS	Dallas	TX
4	7401 SAMUELL BLVD	Dallas	TX
5	1209 BARTON SPRINGS	Houston	Austin