First of all, You NEED to have your registration (username & registration number) saved, or written down or something, and you need the NL setup file that you originally installed it from, as long as you have them, Otherwise I can't help you.
Just back up your tracks and delete NL. Then, reinstall it, but don't change the directory. Next, download the patch to your NL directory and install it. After that, Click NL simulator and type in your registration info again. If you don't have that, I can't help you. Oh yeah, then you can restore your tracks. Enjoy! Hope that works for you, that's what did it for me.
-BBSpeed26
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*** This post was edited by BBSpeed26 on 1/26/2002. ***