Skill : Draw Line 17.2 works , 17.4 doesn't

Hi , 

I am sharing with you some simple skill script that draw line in user layer :

axlCmdRegister("DrawLine" 'DrawLine)
procedure(DrawLine()
   layer_name = "substrate geometry/userlayer"
   mypopup = axlUIPopupDefine(nil '(
      ("Done" "axlDBTransactionCommit(mark), axlFinishEnterFun()")
      ("Oops" "axlDBTransactionOops(mark), when(zerop(--oopsNum)")
      ("Cancel" "axlDBTransactionRollback(mark), axlCancelEnterFun()")
      ("MENU_SEPARATOR", nil)))
   axlUIPopupSet( mypopup)
   ; Clear the dynamic buffer
   axlClearDynamics()

   if(axlLayerGet(layer_name) != nil then
      if(axlIsVisibleLayer(layer_name) == nil then
         axlVisibleLayer(layer_name,t)
         axlVisibleUpdate(t)
      );End if
   else
      if(axlLayerGet("substrate geometry") == nil then
         layer_name = "board geometry/userlayer"
         axlLayerCreateNonConductor(layer_name)
         axlVisibleLayer(layer_name,t)
         axlVisibleUpdate(t)
      else
         axlLayerCreateNonConductor(layer_name)
         axlVisibleLayer(layer_name,t)
         axlVisibleUpdate(t)
      );End if
   );End if

   ; Clear mypath to nil, then loop gathering user picks:
   mypath = nil
   mark = axlDBTransactionStart()
   flag = t
   allP = list(nil)
   seg1 = nil
   seg2 = nil
   while( (mypath = axlEnterPath(?lastPath mypath))
      if(flag == t then
         p = axlDBCreatePath(mypath, layer_name)
         seg1 = car(car(car(p))->segments)
         seg2 = car(cdr(car(car(p))->segments))
         path = axlPathStart( list(car(seg1->startEnd)) , 0)
         axlPathLine( path , 0 , car(cdr(seg1->startEnd)))
         if(seg2 then
            axlPathLine( path , 0 , car(cdr(seg2->startEnd)))
         );end if
         flag = nil
      else
         p = axlDBCreatePath(mypath, layer_name)
         seg1 = car(car(car(p))->segments)
         seg2 = car(cdr(car(car(p))->segments))
         axlPathLine( path , 0 , car(cdr(seg1->startEnd)))
         if(seg2 then
            axlPathLine( path , 0 , car(cdr(seg2->startEnd)))
         );end if
      );end if
      allP = cons(car(car(p)) allP)
   );Loop
   axlDBCreatePath(path, layer_name)
   forall( x allP axlDeleteObject(x))
);End procedure

Is anyone can help to understand why this script can work with 16.5/16.6/17.2 and doesn't work with 17.4 ?

To be more informative in 17.4 this script behaves differently , when i am trying to draw line i can't zoom in/out ,i can't use my shortcuts to snap it on segment/middle/edge , it's like it's waiting only for next X/Y user click , all other functions just disabled .

Thanks .