Russ Archer found a conflict between ACP and Planner 4.2.3 Beta 2 installer. It relates to something that the OLD planner installer does. It will affect people who have Planner 4.1 or earlier installed together with ACP (any version). If you install Planner 4.2 (beta 2) your ACP Plan Compiler object (Plan.wsc) will be gone! Again, the problem is with the OLDER Planner installer. I'm trying to figure out a solution, but since the damage is being done as the older Planner is being uninstalled by the new Planner installer, I'm kind of stuck right now. I clearly don't want to repeat the mistake by installing the ACP plan compiler in this new installer. And it's not simple to hand-install the ACP plan compiler on 64-bit systems. Stay tuned, and I apologize!!