How do I add more thumbs to Albums list

[carlnunes]

By default I get to choose one thumb per album in the list. I would like to display 4 total. I have searched the forum and I have found the code where the thumb is added. Not sure how to add more.
Of course any comments or suggestions are welcome.

[Joachim Müller]

Suggestion: use bbcode or a custom thumbnail instead of trying to fiddle with core code.