I think that if the monster appears but doesn't walk it must be a NODES file problem. Could you please open with notepad++ the NODES file in the CS folder?
They usually look like this:
<AINodes> <Node Name="PathNodeArea_1" ID="123"> <Edge Node="PathNodeArea_6" Distance="1.00000000000000000000" /> <Edge Node="PathNodeArea_7" Distance="2.50000000000000000000" /> <Edge Node="PathNodeArea_2" Distance="3.50891709327697750000" /> <Edge Node="PathNodeArea_5" Distance="4.25000000000000000000" /> </Node> <Node Name="PathNodeArea_2" ID="124"> <Edge Node="PathNodeArea_5" Distance="0.79056942462921143000" /> <Edge Node="PathNodeArea_6" Distance="2.51246881484985350000" /> <Edge Node="PathNodeArea_4" Distance="2.85043859481811520000" /> <Edge Node="PathNodeArea_3" Distance="3.25960111618041990000" /> <Edge Node="PathNodeArea_1" Distance="3.50891709327697750000" /> </Node> <Node Name="PathNodeArea_3" ID="125"> <Edge Node="PathNodeArea_5" Distance="3.16227769851684570000" /> <Edge Node="PathNodeArea_2" Distance="3.25960111618041990000" /> </Node> <Node Name="PathNodeArea_4" ID="126"> <Edge Node="PathNodeArea_2" Distance="2.85043859481811520000" /> <Edge Node="PathNodeArea_5" Distance="3.00000000000000000000" /> </Node> <Node Name="PathNodeArea_5" ID="127"> <Edge Node="PathNodeArea_2" Distance="0.79056942462921143000" /> <Edge Node="PathNodeArea_4" Distance="3.00000000000000000000" /> <Edge Node="PathNodeArea_3" Distance="3.16227769851684570000" /> <Edge Node="PathNodeArea_6" Distance="3.25000000000000000000" /> <Edge Node="PathNodeArea_1" Distance="4.25000000000000000000" /> </Node> <Node Name="PathNodeArea_6" ID="128"> <Edge Node="PathNodeArea_1" Distance="1.00000000000000000000" /> <Edge Node="PathNodeArea_2" Distance="2.51246881484985350000" /> <Edge Node="PathNodeArea_5" Distance="3.25000000000000000000" /> <Edge Node="PathNodeArea_7" Distance="3.50000000000000000000" /> </Node> <Node Name="PathNodeArea_7" ID="129"> <Edge Node="PathNodeArea_1" Distance="2.50000000000000000000" /> <Edge Node="PathNodeArea_6" Distance="3.50000000000000000000" /> </Node></AINodes>
You may delete the nodes and replace them with new ones.