This is a very short sequence, a trifle—hence the "maggot" name. It is suitable as a warm-up dance or for new dancers.
The A part is an adaptation of the Welsh folk dance Robin Ddiog. The Welsh dance is done in a line, no partners needed. Directions for the Welsh dance are available here. It begins with the line dancing to the right (translated here to a circle right) then turning single right.
The "setting" step is also present in the Welsh dance as a sort of syncopated tattoo: LONG-short-LONG-short-LONG-short (right-left-right-left-right-left).
The B part is unlike the remainder of the Welsh dance, which is done in place. Instead, the B part here gives the dance a little of the partner and corner interaction of a progressive couple dance. The partner change is by the left shoulder to flow into the next circle right.