This only seems to happen when I have an object in the layout. If you delete the object, you can delete the layout without the error.
Here's the Cap
http://www.box.net/shared/2d6588f90j
---------------------------
Construct 2 Check failure
---------------------------
Check failure! This is probably a bug:
Project bar: too many layout items in tree
Condition: l != layouts_end
File: Bars\ProjectBar.cpp
Line: 1930
Function: void __thiscall CProjectBar::VerifyLayoutFolderOrdered(const class LayoutFolder *) const
Build: release 30 (32-bit) checked
Component: Construct 2 IDE
(Last Win32 error: 0)
You are using a 'checked' release of Construct 2, intended for testing, which causes potential errors to be reported this way. Hit Ctrl+C to copy this messagebox. Click 'Abort' to quit (unsaved data will be lost!),'Retry' to turn off messages for this session and continue, or 'Ignore' to continue normally.
---------------------------
Abort Retry Ignore
---------------------------