Post the code that does not work.
Generally to turn on cutter compensation you need a linear move that is greater than the radius of the cutter. The message you get suggests you do not have this distance available in your program.
For instance if you had a .500" cutter as tool 1 you would have 0.5 in diameter column (if that is what you have set) in the tool 1 line on the offset page. If you wanted to start cutting at the position X1. Y1. and move toward X1.5 Y1. you should start at something like X0.5, Y1.5.
G00 X0.5 Y1.5 (move to start point)
G41 D01 G01 X1. Y1. F? (enable tool compensation)
X1.5 Y1.
etc
An open mind is a virtue...so long as all the common sense has not leaked out.