I just tried with ActiveSkillsUnassignment=1 but without editing the position (since I play NormRes), and there was an "x" labled button on the skill tabs that worked to return all skill points to that char as if they'd used a respec potion. No keyboard keys were needed. I'm not sure what can go wrong with Plugy, but maybe the position stuff is the culprit (maybe you're not actually clicking the button due to it being off screen or something, sometimes the graphics are just graphics). You might find more help at
PhrozenKeep.