When custom fields are set up each field is given a Name and a Description. When choosing to use the fields in the Event Management and CSV export tabs, only the Description is shown. I have a large number of custom fields named appropriately to reflect their use for different events. The Descriptions are often much simpler and in fact are often repeated between fields. It would be very useful to be able to choose fields by Name rather than Description. Maybe both could be shown?
I've had a ticket open for some time for this same issue. The event management page says Name but displays Description. This makes it difficult to use generic Descriptions unless I remember in what order the fields are listed. I usually don't.
Actually, the description was never shown in Event Management... it was the Label. However as of DT Register 2.5.6, this is changed and shows the unique Name of the custom field. This should help solve your issue.