NTOS Security monitor assertion after first starting Winamp - reproducable (+FS corruption afterwards)

*** Assertion failed: AceSource->Header.AceType == ACCESS_ALLOWED_ACE_TYPE || AceSource->Header.AceType == ACCESS_DENIED_ACE_TYPE || AceSource->Header.AceType == SYSTEM_AUDIT_ACE_TYPE

***   Source File: ../ntoskrnl/se/acl.c, line 468

I can reproduce FS corruption here with reactOS 0.4 RC-1
http://sourceforge.net/projects/reactos/files/ReactOS/0.4.0/ReactOS-0.4.0RC1-iso.7z/download
on VBox4.3.34
with almost 100% certainty by performing these steps:
install Winamp5.666 with default settings.
When Winamp starts for the first time system will hang/BSOD.

After restart I always have a

C:\Program Files\Winamp\system

folder full of crap that can't be deleted.

It is important that "Media Library" is selected during setup to not hide this tickets issue.
It is recommended to deselect "UI interface extensions" to hide CORE-10774 while investigating this.