Integration not working with Simple Control's Simple Sync App

You should be able to add smartthings as a device in Simplecontrol. It’s
under Add Devices → Cloud Services along with Ecobee, Honeywell, Nest,
Insteon… and Smartthings Automation.

Once the device is added and you pair the accounts, you can add smartthings
commands to your simplecontrol activities like any other device. The
command set is a bit limited and shows up as a somewhat oddly formatted
list:

.DOOR LOCK
.DOOR UNLOCK
.LIGHT BRIGTNESS
.LIGHT OFF
.LIGHT ON
.SONOS SPEAK
+WAKEONLAN

Once you select a command you should see your ST devices under Available
Devices.

Hmm… it looks like the blank screen issue that I’m experiencing is known:

Are you following the instructions for the 2015 ST integration here:

http://www.simplecontrol.com/wp-content/uploads/2015/12/SmartThings-Simple-Control-12-2015.zip

I’m trying to remember how this works. It looks like there are two smart
appsa and also a Device Handler:

roomieremote-agent Simple Sync

Do you have all 3?