Unable to access instore

I'm trying to access the instore backoffice with an existing user in the OOTB 6.2 and not able to either use an existing one to access it or create one to be able to do so.

It looks there is an extension called instoresampledata that will generate this users but I do not seem to have this extension included with my current lisencing. Also trying to create a user following instructions here but they are meant for the hmc and I'm not able to actually do the same in backoffice.

Has anyone accomplished to do this and can share how? Any other tips or comments also appreciated.