Custom screen / backdrop window problems

[sodero]

When opening a custom screen with a backdrop window all other windows disappear.

Steps to reproduce:

• git clone https://github.com/sodero/InstallerLG.git
• git checkout axrt_test
• cd build && make -f Makefile.axrt
• Uncomment the (effect) statement in axrt.script
• ./Installer

[deadwood2]

Thanks, I'll take a look at this problem.