EWARM V4.11a

Could i use IAR Embedded Workbench for ARM V4.11A Evaluation version?

EWARM V4.11a

That depends on the port you are using. If using the STR71X port then you can download an older version of the FreeRTOS source code from the SourceForge site.  Check the version change history to find the latest version that saves the projects in a format compatible with EWARM V4.11. If you are using the LPC2000 port then there is no older version with the correct project format and you will have to download an update to your compiler.  The demo will build and execute with the KickStart versions.  I think you can obtain one from the IAR WEB site. Regards.