You need to first obtain the following measurements. Wingspan, Wingtip Chord, Centerline Chord. Average leading edge wing sweep angle, and Wing Area. Plug these values into Kreelin's AeroConvert utility (available in our download secrtion), and you'll have a base line from which to start from, a Cla value.
AeroConvert will than will give you the CLa sum of the entire wing area, which must then be divided by the number of wing panels in the data.ini (2 or 4). In the case of a model with 4 panels (2 outer + 2 inner), I use a 60%-40% value distribution, with the inner panels getting the 60%.
The Xmac tables are calculated from the about 30% back from the leading edge, right where Ymac value starts (Ymac = Mean Area Chord in Y axis. "-" values equal left, plus values equal right). The Xmac "migrates" aft with Mach level, terminating at roughly 50-55 % of the MAC value back from the leading edge.
Hope this hasn't confused or discouraged you.