Linetype Problem

Linetype problem

Via internet I received a drawing file from a fellow to which am having
problems with. The file has a few lines which show up OK and others to
which I cannot do anything with. The whole set of lines needs to be
connected as one big polyline, to which it can't.

I did a simple LIST on the lines  and get these responces.

OK lines:
Angle in UCS XY plane: 90 degrees
Number of Vertices: 4
There are X values and Y values cited and Z is set at 0

Problem lines:
Properties: Open, Non-periodic, Non-Rational, Planar, Non-linear
Number of Knots: 12
Number of control points: 8
There are X values and Y values cited and Z is set at 0

Something about reading the Properties with the problem line wories me.

Wm.