diff --git a/BIN/ASM.S.txt b/BIN/ASM.S.txt
index d0bec5f8..bae883ec 100644
--- a/BIN/ASM.S.txt
+++ b/BIN/ASM.S.txt
@@ -15,10 +15,12 @@ AUTO 6
 *---------------------------------------
 SYM.BLOCK.SIZE		.EQ 4096
 SYM.BLOCK.MAX		.EQ 8
+SRC.IN.DEPTH.MAX	.EQ 7
 *---------------------------------------
 ERR.INV.ARGS		.EQ 1
 ERR.SRC.INV.TYPE	.EQ 2
 ERR.SRC.TOO.LONG	.EQ 3
+ERR.SRC.TOO.MANY.IN	.EQ 4
 ERR.SYM.TOO.LARGE	.EQ 10
 *--------------------------------------
 *			File Header (16 Bytes)
@@ -50,13 +52,6 @@ CS.INIT				>LDYA L.LIBSTR
 					>LOADLIBYA
 					sta hLIBSTR
 					
-					ldy #VAR.INIT
-					lda #0
-.1					sta	(pData),y
-					iny
-					cpy #VAR.INIT.END
-					bne .1
-					
 					ldy #S.PS.hARGS
 					lda (pPs),y
 					bne CS.INIT.ARGS
@@ -156,29 +151,29 @@ CS.DOEVENT			ldy #S.EVT.hDEV		is Event from active IN device?
 .9					sec
 					rts
 *--------------------------------------
-CS.QUIT				ldy SRC.INDEX
+CS.QUIT				ldy SRC.COUNT
 					lda (pData),y
-					bmi .8
+					beq .8
 					
 .1					clc
-					adc #SRC.hREFNUMS
+					adc #SRC.hREFNUMS-1
 					tay
 					lda (pData),y
 					>SYSCALL SYS.MLICloseA
 					
-					ldy SRC.INDEX
+					ldy SRC.COUNT
 					lda (pData),y
 					clc
-					adc #SRC.hBUFFERS
+					adc #SRC.hBUFFERS-1
 					tay
 					lda (pData),y
 					>SYSCALL SYS.FreeMemA
 					
-					ldy SRC.INDEX
+					ldy SRC.COUNT
 					lda (pData),y
 					dec
 					sta (pData),y
-					bpl .1
+					bne .1
 					
 .8					lda hLIBSTR
 					>SYSCALL SYS.UnloadLibA
@@ -190,21 +185,33 @@ LOAD.ASM.T
 					rts
 *---------------------------------------
 SRC.OPEN			sta hFileName
+
+					ldy #SRC.COUNT
+					lda (pData),y
+					cmp #SRC.IN.DEPTH.MAX
+					bne .10
+					
+					lda #ERR.SRC.TOO.MANY.IN
+					sec
+					rts
+					
+.10					lda hFileName
 					>SYSCALL SYS.MLIOpenA
 					bcs .99
 					
 					pha
-					ldy #SRC.INDEX
+					ldy #SRC.COUNT
 					lda (pData),y
 					clc
-					adc #SRC.hREFNUMS
+					adc #SRC.hREFNUMS-1
 					tay
 					pla
 					sta (pData),y
-					ldy #SRC.INDEX
+					
+					ldy #SRC.COUNT
 					lda (pData),y
 					clc
-					adc #SRC.hBUFFERS
+					adc #SRC.hBUFFERS-1
 					tay
 					txa
 					sta (pData),y
@@ -214,16 +221,14 @@ SRC.OPEN			sta hFileName
 					bcs .99
 					
 					>STYA ZPQuickPtr1
-					ldy #1
-					lda (ZPQuickPtr1),y
-					pha
-					
-					ldy #SRC.INDEX
+					ldy #SRC.COUNT
 					lda (pData),y
 					clc
-					adc #SRC.hFILETYPES
+					adc #SRC.hFILETYPES-1
 					tay
-					pla
+
+					ldy #1
+					lda (ZPQuickPtr1),y
 					sta (pData),y
 					
 					cmp #$04			TXT?
@@ -231,14 +236,15 @@ SRC.OPEN			sta hFileName
 					
 					>PUSHBI $0D
 					>PUSHBI $FF
-					>PUSHB SRC.hREFNUMS
+					>PUSHB hFileName
 					>SYSCALL SYS.MLINewLine
 					bcs .99
-
+					bra .8
+					
 .1					cmp #$FA			BAS?
 					bne .98
 
-					ldy #SRC.INDEX
+.8					ldy #SRC.COUNT
 					lda (pData),y
 					inc
 					sta (pData),y
@@ -250,10 +256,10 @@ SRC.OPEN			sta hFileName
 .99					sec
 					rts
 *---------------------------------------
-SRC.ReadLine		ldy #SRC.INDEX
+SRC.ReadLine		ldy #SRC.COUNT
 					lda (pData),y
 					clc
-					adc #SRC.hFILETYPES
+					adc #SRC.hFILETYPES-1
 					tay
 					lda (pData),y
 					bmi SRC.ReadLine.BIN
@@ -336,10 +342,10 @@ SRC.ReadLine.TXT
 *--------------------------------------
 SRC.ReadLine.YA		>PUSHYA
 					>PUSHW L.READ.BUFFER
-					ldy #SRC.INDEX
+					ldy #SRC.COUNT
 					lda (pData),y
 					clc
-					adc #SRC.hREFNUMS
+					adc #SRC.hREFNUMS-1
 					tay
 					lda (pData),y
 					>PUSHA
@@ -414,14 +420,12 @@ READ.BUFFER			.BS 256
 					.DUMMY
 					.OR 0
 DS.START				
-*---------------------------------------
-VAR.INIT
 bSTOP				.BS 1
 bCANCEL				.BS 1
-SRC.INDEX			.BS 1
-SRC.hREFNUMS		.BS 8				Store ref_num of opened files (Main, .INs & .INBs)
-SRC.hBUFFERS		.BS 8				Store hMem to allocated buffers
-SRC.hFILETYPES		.BS 8				Store file type of opened SRC files
+SRC.COUNT			.BS 1
+SRC.hREFNUMS		.BS SRC.IN.DEPTH.MAX	Store ref_num of opened files (Main, .INs & .INBs)
+SRC.hBUFFERS		.BS SRC.IN.DEPTH.MAX	Store hMem to allocated buffers
+SRC.hFILETYPES		.BS SRC.IN.DEPTH.MAX	Store file type of opened SRC files
 
 SRC.LINENUM			.BS 2
 ASM.T.hFILENAME		.BS 1
@@ -429,7 +433,6 @@ ASM.T.hFILE			.BS 1				handle to loaded ASM.T.xxxxx
 DST.hFILENAME		.BS 1
 DST.hREFNUM			.BS 1
 DST.hBUFFER			.BS 1
-VAR.INIT.END
 *---------------------------------------
 ASM.T.FILENAME		.BS 65				PStr ProDOS Max Path Len +1 
 TARGET.FILENAME		.BS 65				PStr ProDOS Max Path Len +1