Of course.

I booked my ticket online with GNV (https://www.gnv.it/en). The price for bike + cabin was 100euros, but there was a 30% sale when I booked.

The day before I contacted them on what time I should be in the harbour. They said 7pm, but it was way too early. So I arrived at 7pm, went to the GNV office to get my ticket here: https://goo.gl/maps/Gqvowbc32KZweexP6
(All of the ferry offices are at this same location)

I got my ticket and rode on to the correct gate (for me it was 13). Then you just follow the line. They had an extra check for me, because I had an Algerian visa in my passport. But other than that, all the standard stuff. They check your passport, your bike papers and the vin number on the bike, they check your luggage and that's pretty much it.

Bringing a drone into Algeria/Tunisia is very Illegal so I do not advise doing it, however I did meet a few bikers in the harbour, one of them might have been carrying a drone inside of his jacket. So if you have something illegal it's better to keep it deep inside your bike or on your person. (I strongly suggest you do not try this, Tunisian prison is not a fun place)

I was done with the procedures at around 9pm and then the waiting to get onboard the ship begun. We waited for many hours and at around 23.30 we were allowed to board the ship. I strongly recommend you bring food and something to do for this long wait. ( I had lots of food and podcasts I could listen to)

On the boat the crew will tie your bikes down securely and the cabins are good and fairly modern.

The process itself was very easy, but the wait was long.

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Update regarding the invitation letter to Algeria:

I have a contact who owns a guest houses in Algeria, who can help you with getting an invitation letter. Please be respectful when you ask her for help. You will have to book a stay at her place in Algiers (or at her Dessert oasis if it's ready, ask about it). You can email her at coachimmo * hotmail.fr