“How can I export all gl transactions to Excel?
(The problem arises since the current reports, which include transaction details, do not include account number on each line and I need that in order to convert the data!)

The record layout needs to be as follows one record for each transaction.
Account number,
transaction date,
source,
description
reference
debit,
credit

This is a trivial operation with GridView. In what way are you trying to convert the data? There is a product you can purchase that will change you g/l account numbers for you directly.