Trouble with adding and deleting I-frames

[kiksenvinnie]

I am having some trouble with Avidemux 2.5.6 trying to create a datamosh effect using this toturial http://datamoshing.com/2016/06/26/how-to-datamosh-videos/

The program do create ekstra I frames, but they dissapper when I export and reopen in Avidemux.
Another problem is deleting the existing few I frames, I can mark them but they wont be deleted. The export do not show any glitching at all.

Ive followed the toturial 3 times with the same result - nothing funny.

Im running Avidemux through windows in virtual machine