G70-G71 issues

I spent a lot of time trying to get the hang of G71, couldn't get my part to run , kept getting a "not monotonic" error when I tried to use what I thought would be simple positioning.  It's pretty much a .375 circle at the inner edge (chuck side) of a piece of thinned down stock to have a smooth transition.  I could only get it to work by using the simpler G2 I have below and G71.1, which worked fine, but then G70 doesn't run the same path.  It wants to do more of the circle, which would create a nasty divot in the part.  I'm pretty far from an expert on coding this stuff, but I have done a few projects over the years, none beat me up so bad   Any good advice / help would be appreciated.

%
g00 g20 g40 g49 g90



g54 g18



g00 z2.5
x.375 

o100SUB
G00 Z 2.5
X 0.25

G1 Z1.5 F300

g2 x.3750 z1.1768 r.1875
o100 ENDSUB

g71.1 Q100  x.375 z2.5 d.01 i.005 f100

//g70 Q100  x.375 z2.5 E0 D.005 f100

%

Thanks, I was going through the list of options and thought I probably should have posted it here in hindsight.