Easy-XL treats row 1 as column headers. Internally, Easy-XL is very much like a database system so when referring to columns by name there may be no arithmetic operators (+-*/^) in the names and names must start with a letter.
If Easy-XL sees any of these operators in the column headers it removes them internally so when you are presented with a list of column names to choose from, you will see the column names as they are used internally. Additionally, if date cells are encountered for column names, Easy-XL converts the date to a text representation and uses that internally.
To get around this, change the data contents (not cell format) of the column header to a fixed text value without any arithmetic operators in it and make sure it starts with a letter or underscore.
I hope this helps.