I tried using the Linework consolidation tool, but I had to attach the two ends of the adjacent lines anyway. Otherwise, it won't work. I thought if one line overlapped the other, it would aoutomatically cut and join the two lines, but not so.
Also tried unify command, but that did nothing. Must be doing something wrong there also.
It seems the solution is to be able to easily join line or polyline segments (contour lines on the merged .dwg file) into one line, but can't figure out how to do it easily. Might have to do it in Autocad, as suggested earlier.
