I played with this setting and it seems to delay the arrival of that ball, but unfortunately does not allow me to start playing before that ball arrive.
I have deleted the apron to see what's going on under the hood, and when the table finish loading there's a ball on the bottom at the location of the "Drain" element, then when the table start working (sound happens) there's a ball that is spawned at the "BallRelease" element while the ball that is at the "Drain" element is deleted. Then the ball at "BallRelease" is pushed in the plunger line.
I moved the Drain element to the middle of the table to see what would happen.
When the table is loaded the ball is still there at the bottom of the table, then when the table start working, the other ball is still spawned at "BallRelease" , but because there's no "Drain" element anymore under the ball on the bottom this one will not be deleted. So at least it confirmed it's not something related to the Drain element.
In the script by editing the bs.Trough setting near the top of the script, it's possible to prevent that unwanted ball to be pushed in the plunger line, but it will still be spawned in "BallRelease" and so will prevent you to start actually playing.
It's very strange and i wonder if the source of this oddity is not in fact in the rom and not in the script.
edit : tried with the andromea.zip rom and it is the same problem.
Then i just tried the VP9 version and there was no erroneous ball spawned when the table start working, seemed good.
But then after pressing F6 to change that 1 ball per game into the more classic 3 balls per games, the VP9 table throw an error.
Hmm, i think this table is just cursed regardless of the VP version, oh well at least there are other tables keeping my attention 
edit 2 : i noticed on the pinballnirvana board, the user ikochnito made dip switches scripts for Andromeda :
https://pinballnirva...274/#post-78664
Sub editDips
Dim vpmDips:Set vpmDips=New cvpmDips
With vpmDips
.AddForm 700,400,"Gameplan Andromeda - DIP switches"
.AddFrame 2,0,190,"Credits per coin",&H0000001F,Array("1 credit - 2 coins",&H000000031,"1 credit - 1 coin",&H00000002,"2 credits - 1 coin",&H00000004,"5 credits - 1 coin",&H0000000A)'dip 1-5
.AddFrame 2,76,190,"Maximum credits",&H06000000,Array("10 credits",0,"20 credits",&H02000000,"30 credits",&H04000000,"40 credits",&H06000000)'dip 26&27
.AddFrame 2,152,190,"High game to date award",&HC0000000,Array("no award",0,"1 credit",&H40000000,"2 credits",&H80000000,"3 credits",&HC0000000)'dip 31&32
.AddFrame 210,0,190,"Replay or free ball award",&H18000000,Array("no award",0,"50,000 points",&H08000000,"extra ball",&H10000000,"replay",&H18000000)'dip 28+29
.AddFrame 210,76,190,"Balls per game",&H00C00000,Array("1 ball",0,"2 balls",&H00400000,"3 balls",&H00800000,"5 balls",&H00C00000)'dip 23+24
.AddFrame 210,152,190,"Specials per game",&H00004000,Array("1 special only",0,"2 specials",&H00004000)'dip 15***
.AddFrame 210,198,190,"Spinner points",&H01000000,Array("start at 100 points",0,"start at 1,000 points",&H01000000)'dip 25***
.AddChk 2,235,150,Array("Extra ball control",32768)'dip 16***
.AddChk 2,250,150,Array("Match feature",&H20000000)'dip 30
.AddChk 2,265,150,Array("Free play",&H00000080)'dip 8
.AddChk 2,280,150,Array("Recall bonus multiplier",&H00000040)'dip 7***
.AddChk 210,250,150,Array("Recall extra ball lane",&H00001000)'dip 13***
.AddChk 210,265,150,Array("Recall spinner value",&H00200000)'dip 22***
.AddChk 210,280,150,Array("Enable extra ball",&H00002000)'dip 14
.AddLabel 30,320,300,20,"After hitting OK, press F3 to reset game with new settings."
.ViewDips
End With
End Sub
Set vpmShowDips=GetRef("editDips")
Replacing the ones in the vpx andromeda script seemed to work for me, it enable more options in the F6 menu.
Unfortunately it does not help with the erroneous ball getting into the plunger line at start
edit : after a few more games it's not even possible to start a new one anymore, even with the wrong ball kicked out, maybe the dip switches went wrong on my test or maybe Andromeda is just cursed ! 
sneak edit : apparently this dip switch script is the exact same that is in the VP9 table (and that will crash the table when you change to 3 balls by game)
EDIT 2 : if somehow this problem does not happen for some other people playing Andromeda, i wonder if the actual source of the problem is that i'm using a recent vpx beta 7 in combinaison with a recent pinmame , hmm maybe i'll have to retry with the default vpx beta 6 and pinmame from the installer and see how it goes
Edited by Robsoie, 20 July 2020 - 05:06 PM.