Switch Engine 33.3.1 is compatible with the version of Extreme Management Center as shown in this table: http://emc.extremenetworks.com/content/common/releasenotes/extended_firmware_support.htm.
Switch Engine 33.3.1 is compatible with ExtremeCloud IQ - Site Engine version 22.3 or later. Older versions (including Extreme Management Center) will not recognize devices running Switch Engine.
Version 33.3.1 was tested with ExtremeCloud IQ Site Engine versions 25.2.12 and 25.5.10.