Thank you for catching this :) just committed the fix for this.
Yes, the major should be (C E G). (C Eb F#) looks like a C dimnished, though I think it would be better written as (C Eb Gb).
True - for some reason I have this affinity to certain notes being sharp and certain ones being flat (i.e. F# > Gb, but Eb > D#), even though the rule is that it should be consistent based on the key.