1 column issue in K2 category listing

Hi,
I see several questions on this forum about the 1 column issue in K2 category listing, but it seems that the solution is not given in public, but on an individual base. That's why I have to ask the same question again. I also would like to have the opportunity to have several columns (probably 4, but depending on the looks etc.) in the K2 category listing layout.
The website I'm working on is still local.
Could you give me the solution to restore the original K2 functionality?
Thanks in advance

Hi

To restore K2 functionality rename /html/com_k2/templates/default/category.php to /html/com_k2/templates/default/_category.php but I'm afraid styling will need some work, since template was locked on 1 column for design reasons.