On FindSpanningTree

Dear members of the group I hope this is the right place to as the following question!
I am using the new function FindSpanningTree to find the a tree with minimum cost. This is,

dg = {0 -> 1, 3 -> 0, 1 -> 2, 0 -> 2, 0 -> 3, 2 -> 3};
dg1 = {0 <-> 1, 3 <-> 0, 1 <-> 2, 0 <-> 2, 0 <-> 3, 2 <-> 3};
Names1 = {Vs, c1, sw1, D1, R2, L};
g = Graph[Thread[Labeled[dg, Names1]], VertexLabels -> "Name"]
HighlightGraph[g, 
 EdgeList[FindSpanningTree[g, EdgeWeight -> {1, 2, 3, 4, 5, 6}, 
   Method -> "MinimumCostAborescence"]]]

The result is

It seems to me that the function failed because the tree includes branch R2, with weight 5, instead of c1 with weight 2.
Is this a bug or I am doing something wrong ?
I have tried also undirected graphs but the obtained tree is not the minimum cost tree. As shown in the following figure.

I will appreciate any help!

Jesus Rico-Melgoza
[1]: /c/portal/getImageAttachment?filename=Tree2.png&userId=67240
[2]: /c/portal/getImageAttachment?filename=Tree.png&userId=67240