I created that example on blog (and YouTube) with 6.0. Now wondering whether 6.1 has disturbed something, didn't check that.
Before 6 it was not possible to have two interactive objects in exact the same place at the same time, even when one was hidden and the other made visible. I discovered that it did work in 6.
Just checked my file in 6.1.319 and the toggle works just fine. But sorry, have really no time now to check your file.
Lilybiri