Did you start Julia with:
julia --project
?
Did you run:
using Pkg
Pkg.update()
?
For the basic examples you might have to change Project.toml to look like this:
[deps]
ColorTypes = "3da002f7-5984-5a60-b8a6-cbb66c0b333f"
CxxWrap = "1f15a43c-97ca-5a2a-ae31-89f07a497df4"
Observables = "510215fc-4207-5dde-b226-833fc4488ee2"
QML = "2db162a6-7e43-52c3-8d84-290c1c42d82a"
ResumableFunctions = "c5292f4c-5179-55e1-98c5-05642aab7184"
[compat]
ColorTypes = "0.11"
CxxWrap = "0.16"
QML = "0.9"
julia = "1.6"
Only required for Julia 1.11, not required for Julia 1.10.