Problems with productpage using grids or 1/5 and 4/5 combinations

Hi!

I have some product categories and in each category I need to show between 3 and 10 products. I need to list the products in the form picture on the left and content on the right….What ever i try (colour section with 1/5 & 4/5 blocks where the 1/5 contains the picture and the 4/5 contains the avia_sc_heading and the avia_sc_text fields) it is not shown correctly.
Sometimes it is displayed as it should, sometimes I see the picture and the description of the first product under the picture followed by html code of the products and pictures which should be shown afterwards.
As I want to use a “splash page” where I see all the categories of the products I thought about using the portfolio as you showed in the sample “Minimal Portfolio”.
I tried to realize the product presentation also with grids instead of 1/5 & 4/5 blocks in a colour section with led me to the same problem.

I cleared my browser caches and checked the page in various broswers (google chrome, firefox, safari….). The problem occurs on any browser. But what confuses me is that it sometimes shows up correctly.

Thanx for information
Herbert