Bit 6 -- Bit7
0 ------ 0 = A
1 ------ 0 = B
0 ------ 1 = C
G Code System A uses G Codes that you're probably more familiar with and is the most prolifically used system.
There are two versions of G71 (G73 in your case) Type I and Type II. Programming both X(U) and Z(W) in your N10 block is the way in which Type II is invoked and the fact that an alarm is raised indicates that your control does not have Type II available.
Type I only permits X moves that are either increasing or decreasing in size in the profile description. In your program snippet, you start X0.95, peak at X1.1 and then finishes at X0.9 within the profile description; this is not permitted.