Idea

In "getReplyDeleteModel" function, localized on "queryhandlers.js" file, there is one wrong variable.

    if(!utils.fileExists(path) || !settings.ModelDeleting || !utils.userHasAccess(req.connection.user, model)) {
        path = settings.modelDirectory + '/' + model + ".fsx";"

"settings" doesn't have any "ModelDeleting" atribute. Instead, it should be "modelDeleting", as folows:

if(!utils.fileExists(path) || !settings.modelDeleting || !utils.userHasAccess(req.connection.user, model)) {
        path = settings.modelDirectory + '/' + model + ".fsx";