Thank you for your comments, Cliff and David
Here's a recording of me playing the piece, with a few mistakes, but then, I only started with transcribing it 3 hours earlier. At my site is a pdf with some extra fingering.
I'll look into those recordings by Grondona.
I wonder why Kindgren changed this to D minor, as the piece is very playable without transposing. Only reason I can think of is the two e's in both voices at the start of measure 3, which he probably changed to a d on the open 4th string and one on the 5th string. I changed the e in the lower voice to g-f#-e an octave lower, although I'm not completely pleased with that either.