Add a leader to a multileader

[Kycau]

Hello.

I have a multileader entity.
I want to add additional leaders to my multileader.
acadObj is the ActiveX object of my multileader.
This is how I made it work for me:
 

(setq muu_lead_vert_new_indx (vla-AddLeader acadObj))
(setq muu_lead_vertices_new (vlax-make-safearray vlax-vbdouble '(0 . 8)))
(vlax-safearray-fill muu_lead_vertices_new (list pt1 pt2 pt3))
(vla-AddLeaderLine acadObj muu_lead_vert_new_indx muu_lead_vertices_new)

It pretty much does the trick, but not as neat as I want it.
If I add multiple leaders, and then I want to work with the new leaders... I search for new leaders via:
 

(vlax-invoke acadObj 'getleaderlineindexes 0)
(vlax-invoke acadObj 'getleaderlineindexes 1)

but 1st command returns '(0), and the second one returns '(1), even if I already have 5 or 8 or 10 leaders on my multileader.

An ugly way around that I found, is the following:
 

(setq sbe_ml_indxlist (vl-sort (append (vlax-invoke acadObj 'getleaderlineindexes 0)
					     (vlax-invoke acadObj 'getleaderlineindexes 1)) '<))
(and (/= (length sbe_ml_indxlist) (vla-get-LeaderCount acadObj))
       (foreach memb '(0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20)
	 (and (not (vl-catch-all-error-p (vl-catch-all-apply '(lambda (x) (vla-GetLeaderIndex acadObj x)) (list memb))))
	      (setq sbe_ml_indxlist (append sbe_ml_indxlist (list memb))))))

The idea is:
I make a list of leader indexes (first 2 lines). In my code I have more lines prior to it... with some verifications... but the idea is that sbe_ml_indxlist in first 2 lines should get all existing leader line indexes.
Next 4 lines, check:
If leader indexes added via vla-AddLeaderLine do not end in the list composed by getleaderlineindexes, I check 1 by 1, if a leader with index X exists, it adds that index to the list of existing indexes.

There are still many problems...  I don't want to get into too much detail... because my post is not about "solving 20 problems"... which result from damaging the multileader entity...
My post is about: "please tell me the right way to add leaders to existing multileader"

Some of extra-problems with multileader on which I did run vla-AddLeader, just fyi:
1. One time I had a multileader with 10+ leaders, but vla-get-leadercount showed 8 leaders. After I copied the multileader, the new one was returning 7 from vla-get-leadercount.
2. If I add leaders via (command "_.mleaderedit" entname "A" $ pause), than the ones added to the left of multileader are seen via getLeaderLineIndexes but the ones added to the right are not seen.
3. Once I had a case that getLeaderLineIndexes did not return 0-index leader... but (getLeaderIndex acadObj 0) showed that such a leader exists, but I can't recreate it.