Dilemma #4

Hey Everyone!!
Again, I apologize for the lateness of this post!!
One of my biggest struggles at this point is making sure I am extremely clear with my students when I try to communicate with them.
I have run into this problem several times, but the time it has been the biggest pain was when I gave them a writing assignment.
My history mentor teacher suggested that I give the students a writing assignment because it would be a good way for me to become familiar with them and the level of their work. He gave me the topic he wanted the students to write about, but that was it. He was hands off with the rest of the process, which I did not realize how involved it can be until I was neck deep in it!!
I did not know what criteria to look for, because I wasn't sure of their writing abilities and my mentor teacher was not clear at all when I asked him for his input. So, I decided I would mark them on: neatness, descriptive, realistic, clarity, and followed directions. For each point they could earn a maximum of three points. In total the assignment would be out of 15 points. This was fine until I was marking the papers and I realized that if students had not handwritten their papers (like they were asked to) then I could not mark them for neatness.. Because about half of them had not handwritten their papers I didn't think it was fair to count this anymore. Also, because their was confusion about the assignment from the get-go because my mentor teacher forgot to post the prompt online (on their version of uLearn) with all the specific instructions...So my rubric was already faulty, but I just crossed out that section and didn't include it. The students could now earn a total of 12 points.
When I went to pass back the papers I explained to the students what they had been marked on and they all claimed that they were not aware that they had been asked to handwrite the papers, so they didn't think it was fair that I counted that portion. Again, because there had been confusion with posting the prompt online I didn't think it was fair to mark them for this... So now they could earn a total of 9 points.
On top of all that, when students got their papers back I attached the rubric which showed where they had either earned or lost points which also had some specific comments of mine about each person's paper. Apparently however, the comments were not specific enough because I had a TON of students coming to me and asking why exactly they hadn't earned points here or there. At that point I had read about 60 different papers over the course of 2-3 days and didn't remember every detail about all of them so I found myself having to re-read all of the papers of those who had questions so that I could explain in great detail exactly why they had earned or lost points.....
Long story short, the marking of these papers was a complete nightmare because the directions weren't perfectly clear...
So, I've slowly been learning this lesson that I have to be EXTREMELY clear with my students.
Has anybody else had this problem? Is this a Dutch student thing...?