Have done this :
Downloaded medikit latest package with size of 35,1 MB.
Went sudo su on my machine and then in terminal called nautilus as root.
Plugged in the usb-stick (ext4) and copied the medikit.tar.gz file to usb-stick with nautilus.
no error-report so far. I switched on internet-modem and waited until boot is finish.
then I switched on turris omnia device and waited after boot is finish - plugged in usb-stick into front sided port. Pressed then the reset-button at rear side until 4 LEDS went red-orange and released the reset-button. Flash went normal and in the end are then 4 white LEDs shining. Duration was about 5 minutes. Then I rebooted turris-omnia and waited if there is an online update patch for 4.0 (because of 4.0.1-release). But there was no online-update of 4.0 for 4.0.1 - (I dont know then if auto-update is disabled ?)
It seems that Flash went alright, but ethernet is not working.
malware-test was negative. there is no virus or malware.
Internet-connection is recognized with all addresses - only in the end of recognition there seems to be lack of hand-shaking for establishing internet-connection ?!
Sorry for my English. (I know only German, English and Sign-Language and somewhat Latin.)