I have 11.1 too but I never actually used kde4.1.3
Right after install I updated to Factory 4.2
I’m sure the cube effect must work in 4.1.3 (unless someone else can confirm otherwise)
In Configure Desktop - Under Look and Feel select - Desktop
Check the box ‘Enable desktop effects’
Look for the ‘All Effects’ tab and make sure you have the ‘Desktop Cube’ selected.