Yes the problem I have often with unclosed, arc or Polylines with dubbel lines (Intersection in Polyline). That why I have a routine which check first if Polyline have a area value, if not it draws a line to them.

`(if (= T (vl-catch-all-error-p (setq A (vl-catch-all-apply 'vla-get-area (list Vobj)))))`

(progn

(princ (strcat "\nwrong area " (cdr (assoc 8 (entget ent))) ))

(setq l (cdr (vl-remove-if-not (function (lambda (x) (= (car x) 10))) (entget ent))))

(entmakex

(list

'(0 . "LINE")

(cons 10 '(0 0 0))

(cons 11 (list (cadr (nth 1 l)) (caddr (nth 1 l))))

'(62 . 256)

(assoc 8 (entget ent))

)

)