Without getting down to the nitty gritty, remember how you program for 3 axis'. You position your cutter, then tell it where to go. the only difference I can find with the 4th axis is that you should take out the backlash of the rotary table. (we do it at our shop anyway.) So, let's review your situation. Position your cutter: X? Y? Move A to -10. then to A0. Position your Z. Now program where you want it to go,G1 X2. A1440.(4 revolutions in 2 inches when pitch = 2) Then move Z up, reposition the rotary to the second cut A80. then A90. Next G1 X2 A1530.(90 degrees + 4 revolutions in 2 inches) Move Z up, reposition the rotary to the 3rd cut. A170. then A180. next G1 X2 A1620. Move Z up. Reposition to the 4th cut A 260. then A270. Next G1 X2 A1710. Move Z up.
Thats the basic idea. You will have to fill in all of the lead-ins and lead-outs, depth cuts,and cutting past the end of the part. Using G1 and stating the x-axis and A-axis in the same line, both axis will get to the end point at the same time, the same as if you programmed a X,Yand Z in the same G1 line.
I hope this helps you.
Good luck, do plenty of practice before actually cutting.