Downloaded the menu and installed, works fine. I made a copy of index and called it index2, I then changed the link on the first menu item to point to Index2, that too works fine.
The problem is on the index page the colour of the font is black and on index2 the colour of font is white
Not without a test page to see what's happening. It could be a style sheet, some style code on the page, it is something with a font color code someplace. Maybe it's pagecolor setting. Without a page, there's no way to know.
We need to see the pages, because I tried doing what you said you did and do not get that problem. Since it seems they are on your desktop, post the code for the index page and the index2 page, then for the menu data file and for any stylesheet if you have one. If you haven't posted code to a forum before, click teh code button then paste the code then click the code button again.
Quick glance... I'd say it's because of pagecolor="white" in your menuStyle. When you're on index.htm, the menu item with url=index2.htm does not match the current page's url. But when you're on index2.htm, the menu item with url=index2.htm does match the current page's url, which triggers the pagecolor property. pagebgcolor would also be triggered. Remove those properties from the stye and you'll have no more page matching.
pagebgcolor and pagecolor are where you set the 'highlighting' If you want your menu to show the user where they are, you would set these colors. Right now you have them set at pagecolor="white" which makes the font white and pagebgcolor=#82B6D7 which makes the background that different blue. Since all your links go to construction.php in the test menu the whole menu will highlight reading that 'matching' for every item
If you leave in the pagecolor and pagebgcolor then any pages that 'match' the particular link you clicked in the menu to get to them will use that as a 'breadcrumb' i.e. highlighting where the person is in the menu. If you don't want that at all, just remove those two items. You can also change the items to whatever colors you want. You can even just use one of them, perhaps you only want the font color to change to indicate where someone is, then just put // in front of the pagebgcolor= part and it will disable it.