VMX42 2011 model with Winmax control.

I posted out some NC code to call up in the middle of a conversational program. The NC merge and industry standard NC options are on the control. It was a trochoidal toolpath and everything worked fine until it gets to a bit where the cutting and repositioning moves are small then it slows down. I'm using a modified Fanuc post from Onecnc without the G54 and G43. There's a look ahead line which is G5.1 Q1. This post works fine on a fanuc control. Am I missing something? Is there a different look ahead setting.