The Simplehomenet Utility Suite is not an HA application, It can perform individual tasks but does not contain the logical functions to independently manage I2CS devices. It does support the checksum aspects of I2CS so it can physically read/write a link record to an I2CS device. However, it does not contain the logic/function to generate the overall environment required to independently establish the I2CS environment required for a PLM to interface with an I2CS device. If the PLM is already authorized to control the I2CS device the SHN Utility can read and write links records but the Utility cannot establish the authorized environment.
Cannot speak to SmartLabs HouseLinc capabilities. The Smarthome Insteon Gold Line support number can likely provide the HouseLinc information.
The Universal Devices ISY does manage Scenes (links) betweens Insteon devices (including the EZX10RF) and other Insteon devices that require I2CS support.