I found I could use the first exercise on the training CD packed with my copy of TC 19 Deluxe. I had problems previously as the Training Guide seems to have been for an other edition with small by significant operating differences.
The exercise involves 3 Centre-lines on a rectangle. The CLs and rectangle are on 2 separate layers.
I tried to apply the same principles to a drawing of my own, but just could not make them work. After I'd realised I should have used TC's Student Template - which might be why I had a lot of trouble with the dimensions - I examined the settings very carefully, made my Layers menu follow the same rules as the templates'.
The Student 2D Template has about 6 layers, with one for the outline, one for centre-lines, etc. I made a New drawing just to make sure I could draw a rectangle with its two centre-lines, with outline and CLs on their own layers.
Yet although my own drawing's tool-bar indicators for the Layer name, visibility-on and colour were all correct, the By Layer sign was on and the Properties seemed to agree, the CLs consistently adopted the outlines' properties. I switched back to the Student Template drawing and verified I was operating it correctly; I verified my drawing's layers menu read the same as in the official template... Sometimes too, I found I could not select the lines I was trying to draw.
So what was wrong to give this strange cross-layer effect?
Also, is it possible to put all the line properties in the layer? If not, editing dimensions' Properties to the consistency and appearance you want, is very laborious.