The place node generated from particle node or inverse placement will automatically switched to "custom" place mode, but if you want to further change the proportion or orientation, you need switch it to position Lock mode which is "PosLock" mode.
In PosLock Mode, our agent placer will still be the same as custom placement but we can change the orientation, proportion
posLoc 
PosLock Mode in Place node
PosRotLock Mode in Place node