Too many layers hides everything

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Visit the demo 
"http://atlasmapper.org/atlasmapperdemo/client/test/index.html"
2. Add a base layer (Google hybrid)
3. Pan and zoom to British Columbia (Canada)
4. Add a lots of layers (ArcGIS helps)
    - asd/base/base
    - asd/eteam/eteam
5. Wait until all the layers are loaded
6. Pan the map up (to see more of the USA)

What is the expected output? What do you see instead?
At some point, the layers start to disappear, the GUI disappear until almost 
nothing is visible.

What version of the product are you using? On what operating system?
1.4.8, on Linux, Chromium browser

Please provide any additional information below.

Original issue reported on code.google.com by lafond.g...@gmail.com on 6 Jan 2014 at 4:59