It's been a long time since I've added resizable to a client, but resizing is not your issue, repositioning is though. From what I remember, you'll need to find in the client class where drawInterface is being called, and change the position parameters to be relative to your game window height & width. Since I don't use resizable clients anymore, I couldn't tell you how to do this. From what I can tell, only your walkable interfaces are having issues, which means that you'll only need to change the positions for where your walkable interfaces are being called to draw.