I've just updated from v2.5.1.0 to v2.5.2.0 SSE2.
While installing I got an error: "Unable to rename Shareaza.exe, Access denied" (Options: Retry, Ignore, Cancel)
and right after that a new error: "Unable to rename Skin.exe, Access denied" (Options: Retry, Ignore, Cancel)
and after that a new error: "Unable to start Skin.exe" (Options: Ok)
The installation left me with a defect shareaza. The resulotion to the problem was to manually delete "Shareaza.exe" and "Skin.exe" from "C:\Program Files\Shareaza" and then install shareaza again.
I have Vista Home Premium - fully updated.