there is info in the MC help file but it has changed a bit
Configure Library Field Settings
Name
The internal name of the field
Display
The name to be displayed in the interface.
Keywords
The keyword that appears in searches. If there are multiple keywords, they must be separated by a semi-colon (without spaces).
Data Type
You can create various types of data, including string, integer, decimal, percentage or a semicolon delimted list.
Category
Where you want the information stored in File Properties (general, extended, audio, display, file info).
Edit Type
Standard. A basic string (like artist, genre, etc).
Clear Only. Select this to clear information that Media Center fills in for you. For example, if your field tracks the number of times something happens (a file is played, etc), you may want the option to clear the information and start over.
Large Value. Long strings, like “Lyrics”. This field uses a popup window for editing.
Cannot be edited. Your field cannot be edited.
Values
Semi-colon delimted list of values you can use (example: 1;2;3;4;5 for rating).
Store in file tags (when possible)
Store the information in the file tag so that it can be read by other software (if supported) or by Media Center upon import.
Default search field
Enable this if you want this field searched when you type something like "dylan" rather than artist=dylan.
Author
Topic: How to create custom fields? (Read 1100 times)