Hello,
These issues are caused by improper layouts of the components. They are clearing clr statements that remove the floats of the columns, these calls are not necessary and are breaking the template's layout:
On this page for example:
http://www.kanarias.pl/index.php?option=com_kunena&Itemid=5Within the source you will see:
<div class="clr"></div>
Just above the div with a class of fb__bt_cvr1
Simply removing the class="clr" will fix this layout, this call is not necessary.
On the other page it is calling a file called helios.css which calls:
#it_tab_menu {
clear:left;
and
#it_tab_menu div.tab {
clear:left;
Both of these calls are causing the issue on this page.