1. Are you using auto-IWT? I mean including IWT in your dps keymaps? Was the thread you found the one I've linked below? Which fix did you try exactly? (For me "move forward" before click-to-move works best but it will break spells with a cast time).

https://www.dual-boxing.com/threads/...unaway-problem

2. Round-robin http://isboxer.com/wiki/Round_robin