Need G Code help

Got the mill up and running and have been getting used to EMC. The main
reason for going to EMC was the cutter comp with G41 G42, that way I
don't have to rewrite the code when I sharpen an endmill. Now I want to
mill a pocket with radiused corners, the following is a bit of the code
I have written along with the problems. I hope the formatting comes
through.
%
m6t1 tool 1 is a 1/2 endmill
g0x10y1 this is a starting hole already drilled
g1z-.25
g41d1y2
g1x8.9y3.25
g3x8.15y2.5r.75 an error comes up "concave corner with cutter radius
comp"
If I change the r.75 to r-.75 it will go with out a quibble but the back
plot shows a loop instead of a radius.
Any help appreciated, if you can point out my backwards thinking and
explain the problem it would be a BIG help. TIA. Ed.