Dimension annotations aligned

I'm trying to dimension multiple part lines in same direction using horizontal dimension tool.
The problem is i can't align adjacent dimensions annotations(so that arrows and text is on the same level).
The reason is my snapping (snap to endpoints) doesn't catch on created dimension annotation for some reason, as if it is not part of the drawing at all!

Any help would be appreciated as i really can't figure out how to do this simple task so that my drawing looks
neat and professional.

Indeed a dimension line doesn't provide any snapping. As a workaround you might use 'snap to grid' and place the dimension line on a grid point. With an aligned or linear dimensioning you will have to use always the very same grid point.
Another idea: on a separate layer draw a line where the dimension shall lie. Back on the dimensions layer position them with 'snap on entity'.  
Best of course would be if LC had a "continued dimension" tool. Sigh...