Unable to run example from package announcement

[EvoArt]

On Julia 1.6.1, in a new environment and after running the code from zigzag.jl, I get the following error when trying to run the example of using ZigZagBoomerang with Soss

julia>     trace, final, (num, acc) = @time zigzag(posterior, T) # sample Soss posterior
ERROR: MethodError: objects of type TransformVariables.TransformTuple{NamedTuple{(:β, :α), Tuple{TransformVariables.Identity, TransformVariables.Identity}}} are not callable
Stacktrace:
 [1] zigzag(m::ConditionalModel{NamedTuple{(:x,), T} where T<:Tuple, GeneralizedGenerated.NGG.TypeLevel{Expr, "Buf{23}()"}, GeneralizedGenerated.NGG.TypeLevel{Module, "Buf{17}()"}, NamedTuple{(:x,), Tuple{Vector{Float64}}}, 
NamedTuple{(:y,), Tuple{Vector{Float64}}}}, T::Float64; c::Float64, adapt::Bool)
   @ Main .\REPL[63]:21
 [2] zigzag(m::ConditionalModel{NamedTuple{(:x,), T} where T<:Tuple, GeneralizedGenerated.NGG.TypeLevel{Expr, "Buf{23}()"}, GeneralizedGenerated.NGG.TypeLevel{Module, "Buf{17}()"}, NamedTuple{(:x,), Tuple{Vector{Float64}}}, 
NamedTuple{(:y,), Tuple{Vector{Float64}}}}, T::Float64)
   @ Main .\REPL[63]:2
 [3] top-level scope
   @ .\timing.jl:210 [inlined]
 [4] top-level scope
   @ .\REPL[65]:0