One way to do this could be to upload all your matches into a database and then pull the positions from this database. And you're in luck! Now there is a way to do that! :-)
Here I have selected all my -0.200 errors I have done in the last few months (since may) (also everything that isn't the correct move is also a -0.200 or bigger error). I can then choose to just view the positions or to play through them answering each position to see if I still make the same mistake or if I have learned from past mistakes.
You could also create challenges based on some action (hit or not, pay now or later etc.) which you can then try and do again at some interval to check if you're getting better or worse at handling these positions.
Or you could play through the existing challenge types which would use only positions from your collection:
I have been thinking about putting something together that will automatically upload an XG file to the server once it is saved from XG. But I haven't found the best way to do that yet (and not worked too much on it either). Batch uploading your matches (I think about 500 at a time is the limit) isn't too bad though.
Now I hope I will soon run out of ideas on what to add to the site so that I can start using it to actually get better at backgammon! :-)
TP
PS. I registered www.backgammonstudio.com today but I'm not sure if everything works as it should yet (seems to do so).