The chord progression of "Waiting in Vain" should not be Cm to C#maj7.
Actually, it might kinda work. I haven't tested it by playing, but I'm thinking this:
C#(maj7) is the same as Db(maj7).
And if the second chord is Db(maj7), then you're in the key of Ab. Which means the first chord should be Ab(maj7).
Cm is actually the upper structure of Ab(maj7). Olivah's basically playing a "rootless" Ab(maj7), which is why it probably sounds correct--especially if one were playing along with a band or recording or something.
JJ