FileBot

I was hoping to use FB as a way to improve automated scraping of a large database. I can't figure out how to modify match probability and highlight movies that are below that probability level, and export nfo files with only imdb url.

FileBot has Strict Mode and Non-Strict Mode but there is no gradient in between that you can configure:
viewtopic.php?t=4695


As for creating NFO or URL files, these are supported, though none of these actions will create NFO / URL files for the selected database, and not IMDb which isn't supported:
viewtopic.php?t=11079


You can include the IMDb ID in the file path though by using {imdbid} in your custom format.