First, let's have a brief overview of what the menu is consisted of so you understand better in order to modify the menu, and know how to fix it if the result is not what you expect.

The menu is consisted of 3 things:
1. Background
2. Button highlights (subpicture layer, invisible in DvdReMake but viewable when playing and in other authoring apps used to customize menus)
3. Button rectangle/markings (red rectangular box as seen in DvdReMake, PgcEdit, and other authoring apps)

The button graphics, aka "button text", is part of the menu background embedded as a video or a still image. The only way to modify this is export the image and edit it in a graphic editor, like Photoshop, and save the result as 24-bit bitmap. The guide explains more in detail.

The button highlights can be seen only if they are in the button rectangles. What you are doing is changing the button rectangle's position to "enclose" the new "button text" of your still menu, when in fact the button highlights are still in its original position. Thus, you don't see any highlights upon playback.

If you are customizing the menu of your own design including different button graphics and position, you should modify the button highlights (extracted using SubRip) to match the button graphic's positions as well. This indicates a complete menu reauthoring. For this, you need to use an authoring tool and follow this guide: http://www.dimadsoft.com/dvdremakepr..._menu_full.php. There are numerous posts regarding this in cdr-zone forum, so search around.