Single Block problems?

[mark c]

Hi all,
Anyone here had problems withMach 2 using single block?
In the past, I've seen some wierd things when single block is on, say at the end of a contour in the ramp out; a partial arc will turn in to a full arc, but at least it knows where it is.
Then on Sat I was machining some slots, had to stop and restart at beginning. By habit I single block to get tool situated then turn it off and let run. It went into slot about .03" deep then took off. Restarted computer then Mach2 and started again. Did first slot went into second slot, about .03" deep then took off to starting point of first slot. It was just G73 chip breaking up to this point. I had already run it past this point.
As an aside I had tried the "run it from here" and couldn't get it to work so I just restarted Mach2 before having these problems.
So......any ideas about single block and what is the secret of the "run from here"?

Thanks in advance

[ktb100]

Single block...reload the software

Run from here..place cursor at the start of the tool.

GL