What may help with the difference in lead is think of the GV as left foot forward (slow) right foot forward same track (slow) left foot side (q) r/f back (q) left foot side (q) r/f forward (q) left foot side together (qq)

As you finish the second quick there is a slight rise and the lead is from the right hand drawing the follow to come with you.

As for the 1/4 turn or senior walk: left foot forward (slow) right foot forward (slow) same track. then the 1/4 turn on the first quick, the whole frame turns to your right as you step to the side together. (almost like cutting the follow off)

hope fully i did not make things worse...

shawn