Yes, you can take a look here (the Powergold import follows the same concept as any other, e.g. the Music 1 import):
viewtopic.php?f=9&t=701&p=2087
In addition you can press the '?' icon at the very top right of the import dialog to get help for each option.
This would for example give the following:
File Format: (Filename Format)
Defines the format of the log filename.
The format defines where to find the year, month and day component within the imported log filename. This is important for the importer in order to recognize the correct Date!
So make sure, that the filename format matches exactly the given log filename!
Use the following placeholders to identify the date components:
yyyy or YYYY: 4-digit year
yy or YY: 2-digit year
MM: 2-digit month
dd or DD: 2-digit day
HH: 24-hour digits
mm: minutes
You might use the '_' or '-' character as a placeholder for any other character in the filename.
The default file format for Powergold is "yyyyMMdd" - so a file called "20161231.asc" would denote the 31st of December 2016 as a date!
The Powergold export format further contains a "StartDateTime" column, which tells the importer the target start time within that day.
I hope this now makes it very clear.