Sorry i have to post this topic here so that i can get quicker response.
I follow this post and with the helps of other i thought i got it working but i think it is not supposed to work that way. Here is the problem.
The post that i am talking about is here Create a theme for a specific flexinode type http://drupal.org/node/31646
i use the following: box_grey theme, flexinode, sections.module.
I want each section of my site to have different look so this is what i did for Products section for example.
Under box_grey theme, i created a folder "Products", copied and pasted page.tpl.php and node.tpl.php to this folder, i renamed node.tpl.php to node-flexinode-1.tpl.php. I turned on Products theme under theme setting.
Under Settings > Sections > I created Products section and select Products theme
Under Settings > Content > Content Types > i created new conent type and this would be flexinode-1 and i named it productscontent
Create conent > productscontent > and add this to Products Category
Anyhow, Products section is displayed correctly using Products theme page.tpl.php. It is however when i clicked the page, the page is displayed but it did not use node-flexinode-1.tpl.php under Products theme instead it uses node.tpl.php of box_grey theme.
I corrected the problem by copy and paste a copy of node-flexinode-1.tpl.php and place it under box_grey. the content page is correctly used node-flexinode-1.tpl.php under box_grey theme but it is embedded in page.tpl.php of box_grey theme.