I am not aware, did not notice a single thing going wrong using 10 the way I need to. But then again, most of the time I know what I am doing...
This is an old issue reported many times on the web. The problem occurs when searching thru the registry and when registry data are longer than 255 bytes (of course, this does't occrur for everybody). One can get around by using the regedit version from 10240 or a utility like regscanner. MS made many changes between 10240 (size : 133 kB) and 10586 (size : 293 kB) and what I blame is that MS didn't correct the issue after several weeks.