Categories home

Hello,

I'm trying to rewrite the 'Categories Home' extension by eatblueorange:
http://www.opencart.com/index.php?route ... order=DESC

The module uses radiobuttons to select the category you want to display on the homepage. As I want to be able to choose several categories I changed these to checkboxes with name=categoryhome_category[] so the output is an array. I try to save the output array as a string with an implode-function. However I can't seem to get the system to save this output in the database. (post resolve works fine, I get no errors). Any clue/tip would be most appreciated.

Thanks.