Transpose exercise to all 12 keys

I have a little 4-bar exercise in Bb I want to transpose into all 12 keys. So the first one I just copy paste and then transpose to the next key which would be B. So it does it, but does not set new keysig, so everything is accidentals. Well OK and I drag the 5#'s keysig into the first bar of the new one and good all the accientals go away and the chords are transpose perfectly and everything is good. WOO HOO THIS IS A PIECE OF CAKE. NOT SO FAST.
So the next key is C. So I try copy paste the first one and transpose to C and it goes all crazy. For example the first note of the model one is F -- the 5 degree of the scale, then in B it should be (and is) F#, and in C it should be G. But no it makes it a C and all the notes and chords are wrong. Did it twice just to be sure it wasn't my mistake. Workaround was to create a temporary file, transpose to each key copy in and drag in the appropriate keysig. Kinda klunky. WTF was it thinking??? Just curious.

Also on my machine (Mac) in the keysigs palette I can only see 5 flats for the Gb one, even though the scrollover is correct an if you drag it it does indeed do 6 flats. But while doing it quickly I mistook it for Db I didn't realize you can scroll the whole palette over to see it all.