DXF code access via LISP and Mleader background masks

OPAdrafting
OPAdrafting
in LISP

I'm running a pretty old version of Brics "21.2.07". I only do 2d processing and CAD/pdf deliverables for utility locating companies.

I've had a number of fringe issues, mostly with dynamic blocks and how they behave going from Brics to Auto, they've never been addressed and when I have tried new Brics product they still remain, so I've never bothered updating, I just workaround the issues.

One of the things that's always bugged me is the ability to create a MLeader with the background mas on and set as drawing background colour. In Auto this works:

(defun C:MLEADERFILL ( / )

	(varopen)


(SETQ LLEADER (ENTLAST))

 	(setpropertyvalue LLEADER "MText/BackgroundFill" 1)


	(varclose)


(princ)
)

Obviously I can't access the same toggle in the Brics OS, so after much searching, failure, and research I got this from another user on ACAD forums:

(defun c:mlmon (/ mld_dxf 1_2_dxf 2_2_dxf)
(setq mld_dxf (entget (car (entsel "\nPick Mleader: "))))
(setq 1_2_dxf (member '(302 . "LEADER{") (reverse mld_dxf)))
(setq 1_2_dxf (reverse (cdr 1_2_dxf)))
(setq 2_2_dxf (member '(302 . "LEADER{") mld_dxf))
(entmod (setq mld_dxf (append (subst (cons 292 (if (zerop (cdr (assoc 292 1_2_dxf))) 1 0)) (assoc 292 1_2_dxf) 1_2_dxf) 2_2_dxf)))
(if (equal '(141 . 0.0) (assoc 141 mld_dxf)) (entmod (subst '(141 . 1.5) '(141 . 0.0) mld_dxf)))
(princ)
)

Why does this not work in Brics? How can I create the Mleader in Brics and then open the drawing in Auto and use the above but it doesn't work in Brics? It seems counter intuitive that the dxf code tables are inaccessible for digital entities in Brics when the tables are written by Brics and I'm accessing them via LISP.

Can I get an explanation of why Brics prevents this? I've checked other forum posts, IIRC the last was 2024, so I assume it's still inherent in the OS, and the issue is buried deep in the OS and is why there's no Brics express tool to perform the function from the ribbon. Is there any thought about fixing the issue going forward?

If your wondering why I'm even asking, after all Qselecting all MLeaders and turning the BG on from properties is easy right? Apparently it's literally the worst thing that could ever happen if you used ACad and are now "forced" to use BricsCAD, or so I'm told.