diff --git a/Project.toml b/Project.toml
index c792615..46e8d9c 100644
--- a/Project.toml
+++ b/Project.toml
@@ -11,7 +11,7 @@ TensorCrossInterpolation = "b261b2ec-6378-4871-b32e-9173bb050604"
 
 [compat]
 BitIntegers = "0.3.5"
-QuanticsGrids = "0.3"
+QuanticsGrids = "0.3, 0.6"
 TensorCrossInterpolation = "0.9.16"
 julia = "1.6"
 
diff --git a/src/tciinterface.jl b/src/tciinterface.jl
index edb7dec..45baf9c 100644
--- a/src/tciinterface.jl
+++ b/src/tciinterface.jl
@@ -75,13 +75,7 @@ function quanticscrossinterpolate(
     nrandominitpivot=5,
     kwargs...
 ) where {ValueType,n}
-    R = grid.R
-
-    qlocaldimensions = if grid.unfoldingscheme === :interleaved
-        fill(2, n * R)
-    else
-        fill(2^n, R)
-    end
+    qlocaldimensions = QG.localdimensions(grid)
 
     qf_ = (n == 1
            ? q -> f(only(QG.quantics_to_origcoord(grid, q)))
diff --git a/test/test_fouriertransform.jl b/test/test_fouriertransform.jl
index 6f3cdc2..4bb6a1b 100644
--- a/test/test_fouriertransform.jl
+++ b/test/test_fouriertransform.jl
@@ -3,25 +3,52 @@ import TensorCrossInterpolation as TCI
 import QuanticsGrids as QG
 import Random
 
+"""
+    function index_to_quantics!(digitlist, index::Integer; base::Integer=2)
+
+* `digitlist`     base-b representation (1d vector)
+* `base`           base for quantics (default: 2)
+"""
+function index_to_quantics!(digitlist, index::Integer; base::Integer=2)
+    numdigits = length(digitlist)
+    for i = 1:numdigits
+        digitlist[i] = mod(index - 1, base^(numdigits - i + 1)) ÷ base^(numdigits - i) + 1
+    end
+    return digitlist
+end
+
+"""
+    index_to_quantics(index::Integer; numdigits=8, base::Integer=2)
+
+Does the same as [`index_to_quantics!`](@ref) but returns a new vector.
+"""
+function index_to_quantics(index::Integer; numdigits=8, base::Integer=2)
+    digitlist = Vector{Int}(undef, numdigits)
+    return index_to_quantics!(digitlist, index; base=base)
+end
+
+#@testset "Quantics Fourier Transform, R=$R" for R in [4, 16, 62]
 @testset "Quantics Fourier Transform, R=$R" for R in [4, 16, 62]
     Random.seed!(23593243)
 
+    grid = QG.DiscretizedGrid{1}(R, 0, 1)
+
     r = 12
     coeffs = randn(ComplexF64, r)
     fm(x) = sum(coeffs .* cispi.(2 * (0:r-1) * x))
-    fq(q) = fm((QG.quantics_to_index_fused(q)[1] - 1) / 2^big(R))
+    fq(q) = fm(QG.quantics_to_origcoord(grid, q)[1])
 
     qtci, = TCI.crossinterpolate2(ComplexF64, fq, fill(2, R); tolerance=1e-14)
     fouriertt = QTCI.quanticsfouriermpo(R; normalize=false) / 2^big(R)
     qtcif = TCI.contract(fouriertt, qtci)
 
     for i in 1:min(r, 2^big(R))
-        q = QG.index_to_quantics(i, numdigits=R)
+        q = index_to_quantics(i, numdigits=R)
         @test qtcif(reverse(q)) ≈ coeffs[i]
     end
 
     for i in Int.(round.(range(r+2, 2^big(R); length=100)))
-        q = QG.index_to_quantics(i, numdigits=R)
+        q = index_to_quantics(i, numdigits=R)
         @test abs(qtcif(reverse(q))) < 1e-12
     end
 end