Synology just released another update for DSM.
Synology has released a new version of DSM and I can confirm that it’s working on the latest Xpenology boot image (5.2-5644.5). Just upgrade from the user interface, but make sure that you are not accidentally upgrading to DSM 6.
Update 02.05.2016: Hardware & Power settings seems to be broken in this build. I recommend you wait for a new boot image before upgrading past DSM_5.2-5644
Version: 5.2-5967 (2016/04/28) What's New This update includes all bug fixes as well as security fixes in the previously released updates since DSM 5.2-5644. Fixed Issue Improved performance of backup tasks and data restoring in Backup & Restore. Improved backup stability in Backup & Restore when files are being edited. You may now choose to reset the system without resetting the password at Control Panel > Update & Restore. Added full-speed fan mode to provide the best cooling effects for Synology NAS. Fixed multiple vulnerabilities regarding Samba module (CVE-2016-2118, CVE-2015-5370, CVE-2016-2110, CVE-2016-2111, CVE-2016-2112, CVE-2016-2113, CVE-2016-2114, CVE-2016-2115). Fixed an issue where iSCSI service could not start upon system boot with snapshot retention policy enabled in DSM 5.2-5644. Fixed an issue where iSCSI service could not respond under certain conditions when LUN was being created or removed. Fixed an issue where the system could not enter hibernation with Snapshot Manager for VMware registered. To enhance the security level, Synology's default administrator account "admin" with the blank password will no longer be allowed and will be disabled after this update. It is also highly recommended that you increase the password strength of all accounts belonging to the administrators group. Fixed an issue where permission settings for a shared folder could not be edited in Windows if the folder was mounted via SMB.