These days I just use it for a few directshow filters (like Divx-antifreeze) and nothing else. I began to notice a few users having similar symptoms such as in the Avs Scripting Thread. If you uninstall Nimo be sure to reinstall the AMV pack and if you had it install the codecs reinstall those with their own respective installers.
Even if you uninstall it and didn't have the AVIsynth frameserver checked originally when you installed you need to reinstall the AMVapp as it removes or alters the needed files... Another reason it's evil

Oh and this isn't related to editing but Fraunhofer mp3 decoder in it conflicts with the game No One Lives Forever 2 Fraunhofer decoder and the game won't have sound unless you uninstall them both and reinstall NOLF2...
This topic refers to nimo5.0 build 8. I'm not sure if it is the same for other versions or builds but it is quite conceivable..