Virtuemart category module does not show on all categories and products 2.6.10

[stawebnice]

Hi,

I have an eshop in VM 2.6.10 with Joomla 2.5.27. I assigned the module virtuemart categories to the Virtuemart front page menu item: http://imtp.me/8f2m0250b.p

but the menu is shown only on categories view:
http://www.bowling.stawebnice.com/eshop-bowlingove-potreby


It is not shown in all 1st level categories: http://www.bowling.stawebnice.com/bowlingove-koule
http://www.bowling.stawebnice.com/bowlingove-boty etc.

however, it is on some 2nd level categories: http://www.bowling.stawebnice.com/bowlingove-koule-affordable-performance

and some products: http://www.bowling.stawebnice.com/bowlingova-taska-na-jednu-kouli-flash-single-royal-modra  (it is shown on some bowlingové koule subcategories and their products though:
http://www.bowling.stawebnice.com/bowlingove-koule-affordable-performance
http://www.bowling.stawebnice.com/bowlingova-koule-damage

I have even tried creating a menu item for the 1st level category bowlingove koule and assigned the menu there, but no result for the first level category: http://imtp.me/8f2o0250b.p

Please advise what is wrong and how to fix it...