Hi Garabo,
I tried but with no result.
I copy the two files (MQXRtosPlugin.ewplugin and MQXRtosPluginARM.dll) from my installation folder C:\Data\Freescale MQX 3.7\tools\iar_extensions\Embedded Workbench 6.X\arm\plugins\rtos\mqx to IAR folder C:\Program Files (x86)\IAR Systems\Embedded Workbench 6.0\arm\plugins\rtos\MQX.
As you can see in a picture of my previous answer, I think the problem is plugin version I have in my MQX 3.7 installation package.
On MQXRtosPluginARM.dll file -> right click -> properties -> i have version 4.4.1(CSpy 6.x, FLSMQXOS 3.6.1)
I think I need FLSMQXOS 3.7.0 but I can't find it.
Do you have my configuration (IAR 6.1 and MQX 3.7.0)? Your TAD is ok? If yes, can you please look at your MQXRtosPluginARM.dll properties?
Many thanks,
Corrado