Long story short: Made a simple mod that alters the Smithing perk tree. Took me maybe an hour or two once I had figured out what I wanted to do. But, without realizing it, I had Dawnguard loaded as a master file in the Creation Kit (in addition to Skyrim/Update), so it now requires Dawnguard to function. The mod doesn't actually use anything Dawnguard-related, so I'm wondering if there's an easy way to rid it of its Dawnguard dependency short of doing the mod over again without Dawnguard loaded. Thanks!