Today, I had the problem of converting a timestamp to a readable time format inside excel. Not quite as easy as I would have hoped for, but the solution is fairly painless.
In the excel column you wish to display the date, you need to place the following formula.
You would then need to replace COLUMN_ID_HERE with the cell that holds the timestamp. e.g. A1
The above formula can be simplified, but I think the above explains a little more what is actually being done to the data
You would then need to format the cell to be dd/mm/yyyy hh:mm and you are done