This is a small patch that edits some greeting conditions for vampires in Vvardenfell.
This was created to work with the vampirism mods like Blood is Everything. It should work with any mod that lets you hide your vampiric appearance (seen in BIE as a "Bare Fangs" lesser power). It is not dependent on anything other than Morroblivion to work.
Morroblivion, pulling from original Morrowind, prevents you from interacting with most NPCs as a vampire, causing disposition drops and in some cases starting combat. This small patch adds a check for your current vampirism actor value. As long as it's under 25 (vanilla Oblivion's "Stage 1/25% Vampirism"), NPCs will interact with you as normal.
Without any vampire overhaul mods, this mod will work but be effectively useless as you cannot be below 25% vampirism without curing it.
If anyone wants to modify this patch (such as changing the actor value threshold) for their own use in the Construction Set, all changes are made to the topics of the journalless "fbmwVampireGreetings" quest. Currently, greetings from Mages (who can point you to a cure), other vampires, and the servants of Irarak in Ginith Ancestral Tomb are unaltered.