How to colour columns based on timestamp or on author_link

I'm trying (without success) to colour columns based on:

1) timestamp in order to mark those books added today (something like: "format_date(now(), 'yyyy-MM-dd') == {timestamp:format_date( 'yyyy-MM-dd')}")

2) the "author_link" to mark those authors who have a custom link added through manage authors (something like: "author_link:true")

Could anyone help me with the appropriate templates.

Thank you all.


Version info:
Calibre 0.9.5
Language: Spanish
OS: Windows XP