Hi @jongminiga,
I have corroborated this behavior on my side. GUI Guider 1.9.0 indeed gets stuck on "Creating Project" status when setting a custom panel of 1280W x 720H. I will report this issue to the GUI Guider team.
That said, this issue is not present on GUI Guider 1.8.1, so please use that instead for now.
BR,
Edwin.