I upgraded to 7.x-2.0-beta1+76-dev, it recommended using the 2.12 version of the OL libraries so I moved to that and encountered 2 problems. Apologies if they aren't related to each other and should have been logged as two separate issues...
To confirm and narrow down the problems I used a blank Drupal installation with only the basics needed for OL and I could reproduce the following problems:
1) I found that when I create a KML layer it seems to save the data to the database (checked in the DB directly) but when I attempt to edit the layer properties the URL is blank. The same happened with a GeoJSON layer; everything other than the title and description was shown as empty despite their values being stored in the DB.
2) Using the old OL libraries (2.11) I found that these layers still appear as normal on a map, but when I use OL 2.12 the KML layers failed (the whole map appears as a white canvas). To rule out a problem with my KML file I tried using the "sundials" example kml file (referenced here: http://dev.openlayers.org/releases/OpenLayers-2.12/examples/sundials.html); and it had the same problem (fine with 2.11, causes the whole map to fail in 2.12).
Hope this is enough info to indicate what the problems are...
BTW; great module - keep up the good work :-)