Hello,
I am using Joomla 1.6 and JoomDOC 3 dowloaded three days ago.
The problem I had was that the download hits counter did not want to increase.
The problem I found in JoomDOCModelFile.saveHits method, where the conditions for updates uses a condition to a version that was always 0, but in the database all the records are set up as version 1.
That's why the hit counter never increased.
I made a correction, do not give the version contition when the version parameter has a null value.
Description of the fre version is not using versions. I hope that this is the solution.
If you have the same problem, yopu can try to the same as me.

Hello, thanks for the bug report, we will fix this.