Unable to do control left click (and hold ) to click (and hold)

Hi there, in some CAD software it is important to used control + left click and drag. However, Mac OS does not allow that to happen and remap control-left click to a right-click and I won't be able to drag. I tried to add a pair of items under the normal mouse category, one is triggered when ctrl + click (down) = custom click left, and the other is triggered when ctrl + click (up) = custom click left. It did the job handling clicks but not drags. Any suggestions?