Grisaille technique learning curves

I got to work on my class painting Friday. I finished outlining my charcoal drawing with raw umber and mineral spirits and waited for it to dry before toning the canvas with a coat of light red oil paint mixed with half/half mineral spirits and linseed oil. It kind of got away from me and turned out really orange and not too transparent and some of the charcoal lines didn't disappear with the paint, even though I had tried to erase them before toning. I figured it might be a good idea to have a canvas in reserve in case this one didn't work, so I decided to do a copy of Velazquez's "The Immaculate Conception." Since I had some technical problems with getting rid of the charcoal under-drawing on the first painting, I projected the image onto the canvas like a few of the students had done in the class. I guess I'm not very mechanically inclined because that didn't go well either. I had a heck of a time getting it to project properly on the canvas. For some reason, I could only get the top half of the image no matter what I did. So I ended up doing the bottom part of the image freehand, but with draperies it shouldn't be a big deal. However, when I tried to tone the canvas over the raw umber drawing, a lot of the image washed off. There are a lot of technical issues to deal with in this grisaille technique and I hope I can catch on.

I did find an interesting book while Googling the term grisaille. It's called "The Secret of the Old Masters" by Albert Abendschein, published in 1906. I'm reading through it whenever I get some time, which isn't often. I like reading old books because of the flowery language they tended to use back then and it also has some good insights into the technical aspects of painting in oil and why so many old paintings have deteriorated into a shell of their former glory.