CC3220SF-LAUNCHXL: save the FW in the on-board flash memory

Hi WiFi team

I'm developping a custom FW for CC3220SF device (by now I'm using the CC3220SF Lauchpad)

The SDK version is 6.10

Till today I worked with Code Composer Studio (ver 12.1), in debug mode, without issues

Now I would like to save the FW in the on-board flash memory, but I'm stuck

If I well understand, the CC3220SF executes a secure boot, then the FW must be "signed"

Opening the image.syscfg file in the project root folder,

• at the item "Certificate Store", I see "Certificate Catalog" --> Use dummy root cartificate playground from SDK
• at the item "MCU Image", the flags checked are "Failsafe, Secure, Public write" and "Security Sign Mode" is "Simple"

With this configuration (and the SPO jumper in position 1), when I build the progect in MCU+Image mode, the console reports these messages

**** Build of configuration MCU+Image for project FOO ****

"C:\\TI\\ccs1210\\ccs\\utils\\bin\\gmake" -k -j 8 all -O

gmake[1]: 'FOO.out' is up to date.
Building secondary target: "syscfg/FOO.sli"
Invoking: Image Creator
"C:/TI/simplelink_cc32xx_sdk_6_10_00_05/source/ti/drivers/net/imagecreator/bin/SLImageCreator.exe" syscfg create_image --sdk_path "C:/TI/simplelink_cc32xx_sdk_6_10_00_05" --json "C:/workspace/FOO/MCU+Image/syscfg/ti_drivers_net_wifi_config.json" --file "C:/workspace/FOO/MCU+Image/syscfg/FOO.sli" --mcu "C:/workspace/FOO/MCU+Image/FOO.bin"
INFO:root:FTDI not detected, trying XDS
INFO:slbootloader.slbootloader:Connecting to device
INFO:slbootloader.slbootloader:Power off
INFO:slbootloader.slbootloader:Set break signal
INFO:slbootloader.slbootloader:Power on
INFO:slbootloader.slbootloader:Clear break signal
INFO:slbootloader.slbootloader:Connection succeeded
INFO:slbootloader.slbootloader:Received storage list

Copyright 2014 TI.com. All rights reserved, SimpleLink programming image builder
Builder = 3.0.1.6
Interface version = 1.0.2.16
Recommended command line window resolution W124 X H67
The output directory is :[C:/workspace/FOO/MCU+Image/syscfg\sl_image]
The XML file is :[C:/workspace/FOO/MCU+Image/syscfg\sl_image\ImageConfig.xml]
Validate the XML against the schema.
The XML validation passed.

** here I see the list of CommandWriteFile for all saved files **

Finished successfully.
Finished building secondary target: "syscfg/FOO.sli"

I suppose that the FOO.sli file in syscfg folder is the final image

For download this image into the memory target I run UniFlash (ver 8.1) and I click the Program Image button

• in the "Image file name" I add FOO.sli 
• but what should I add in the "Imag Key File Name" field?

If I leave this second field blank, the programming is successful without errors, but my FW doesn't start

Trying to understand the cause, I noticed that in the folder "MCU+Image/syscfg/sl_fs/sys" there are mcuflashimg.bin and mcuflashimg.bin.bin; it's normal?

Thanks a lot fo your support

Andrea