I did the win8x64 40 dollar pro upgrade from win7 December 14th.. and have had your second Event log item ever since. I've reinstalled the win8 every way I could think of to try to eliminate it.. with no luck.
This is on a Lenovo g570 budget laptop i3 sandy bridge 2nd gen cpu with the combined/intergrated intel 3000 graphics.
event id 1530
Windows detected your registry file is still in use by other applications or services. The file will be unloaded now. The applications or services that hold your registry file may not function properly afterwards.
1 user registry handles leaked from \Registry\User\S-1-5-21-976289058-815564480-4253628741-1001:
Process 384 (\Device\HarddiskVolume2\Windows\System32\svchost.exe) has opened key \REGISTRY\USER\S-1-5-21-976289058-815564480-4253628741-1001\Software\Microsoft\Windows\CurrentVersion\Uninstall
(also has another persistant event - Kernal-PnP event id 219, The driver \Driver\WUDFRd failed to load for the device ROOT\LENOVOVHID\0000. but it is truly loaded )