Hi Guys,
Myself I prefer the approach number 3 which is to use !important to override the float:left;
But I can shed light on why it is not working when he adds UseNet35Mode, it is because of using UseArtisteer="true" on the PageMenu, that is the old way we supported Artsiteer and it uses a different menu control than mojoMenu. In more recent versions we no longer use that setting because we have configuration properties on mojoMenu that allow it to render what is needed for Artisteer, so the older ArtisteerMenu is now deprecated but is still there for backward compatibility with existing skins.
If you look in recent version Artisteer skins you will see that we don't use the UseArtisteer attribute anymore on SiteMenu or PageMenu, instead we configure mojoMenu from theme.skin like this:
<portal:mojoMenu runat="server" SkinID="SiteMenu"
RenderContainerCssClass="true"
RenderImages="false"
UseMenuTooltipForCustomCss="true"
RenderCustomClassOnLi="true"
RenderCustomClassOnAnchor="false"
RenderLiSelectedCss="false"
RenderAnchorSelectedCss="true"
UlCssClass="art-hmenu"
LiCssClassWithChildren=""
LiCssClassWithoutChildren=""
LiSelectedCssClassWithChildren=""
LiSelectedCssClassWithoutChildren=""
LiChildSelectedCssClass=""
LiParentSelectedCssClass=""
AnchorCssClass=""
AnchorSelectedCssClassWithChildren="active"
AnchorSelectedCssClassWithoutChildren="active"
AnchorChildSelectedCssClass=""
AnchorParentSelectedCssClass=""
InnerSpanMode="Artisteer"
/>
You could then add the UseNet35Mode there if you want to.
Hope it helps,
Joe