Got problems after update to 2.x build 341

[Phantom]

I have updated my Sencha Designer to v2.0.0 build 341
Now when I try to change a value of some properties in "Config" panel i receive errors like

TypeError: 'null' is not an object

Got such when i tried to change 'region' property of a panel as well as when i tried to add an event handler to Ext.menu.DatePicker component.

[ashapiro75]

I'm getting it when I try to set up my project settings on a PC, thankfully my mac hasn't updated yet.