diff --git a/apps/ed/Makefile b/apps/ed/Makefile
index 6890630..7a05556 100755
--- a/apps/ed/Makefile
+++ b/apps/ed/Makefile
@@ -41,10 +41,14 @@ APP_COMMON_DIR = $(CURDIR)/../common
 BASEDIR        = ../../..
 
 # Override values given by parent make for this application as its memory usage differs from the standard app.
+# Only apply for ZPU builds - these addresses are within the ZPU's unified BRAM address space.
+# K64F uses the default heap/stack calculated by build.sh which fits within the Cortex-M4 SRAM regions.
+ifeq ($(__ZPU__),1)
 override HEAPADDR  = 0x1FFF5000
 override HEAPSIZE  = 0x00033000
 override STACKADDR = 0x20028000
 override STACKSIZE = 0x00000000
+endif
 
 # Modules making up Kilo.
 APP_C_SRC      = $(APP_COMMON_DIR)/sysutils.c $(APP_COMMON_DIR)/ctypelocal.c
diff --git a/apps/kilo/Makefile b/apps/kilo/Makefile
index f585d12..b2934e0 100755
--- a/apps/kilo/Makefile
+++ b/apps/kilo/Makefile
@@ -41,10 +41,14 @@ APP_COMMON_DIR = $(CURDIR)/../common
 BASEDIR        = ../../..
 
 # Override values given by parent make for this application as its memory usage differs from the standard app.
+# Only apply for ZPU builds - these addresses are within the ZPU's unified BRAM address space.
+# K64F uses the default heap/stack calculated by build.sh which fits within the Cortex-M4 SRAM regions.
+ifeq ($(__ZPU__),1)
 override HEAPADDR  = 0x1FFF5000
 override HEAPSIZE  = 0x00033000
 override STACKADDR = 0x20028000
 override STACKSIZE = 0x00000000
+endif
 
 # Modules making up Kilo.
 APP_C_SRC      = $(APP_COMMON_DIR)/sysutils.c $(APP_COMMON_DIR)/ctypelocal.c
diff --git a/apps/mbasic/Makefile b/apps/mbasic/Makefile
index 12f389d..e04fe8c 100755
--- a/apps/mbasic/Makefile
+++ b/apps/mbasic/Makefile
@@ -43,6 +43,8 @@ COMMON_DIR     = $(CURDIR)../../common
 BASEDIR        = ../../..
 
 # Override values given by parent make for this application as its memory usage differs from the standard app.
+# mbasic only builds on K64F (ZPU build disabled due to missing maths libraries).
+# These overrides extend the CODE region to encompass the larger heap needed by the BASIC interpreter.
 override HEAPADDR  = 0x2000C000
 override HEAPSIZE  = 0x0001BC00
 override STACKADDR = 0x20027C00
@@ -62,7 +64,15 @@ FILTER2        = $(filter-out $(filter HEAPSIZE=%,$(FILTER1)),   $(FILTER1))
 NEWMAKEFLAGS   = $(FILTER2) HEAPADDR=$(HEADADDR) HEAPSIZE=$(HEAPSIZE)
 
 ifeq ($(__K64F__),1)
-include        $(APP_DIR)/Makefile.k64f
+# Currently mbasic doesnt build on K64F - heap/stack overrides exceed the app CODE region.
+# TODO: Rework memory layout to fit within K64F SRAM constraints.
+#include        $(APP_DIR)/Makefile.k64f
+clean:
+
+all:
+
+install:
+
 else
 # Currently mbasic doesnt build on the ZPU due to missing maths libraries. Once I can source them it should build.
 #include        $(APP_DIR)/Makefile.zpu
diff --git a/apps/tbasic/Makefile b/apps/tbasic/Makefile
index 6021f2a..79d70a9 100755
--- a/apps/tbasic/Makefile
+++ b/apps/tbasic/Makefile
@@ -41,10 +41,14 @@ APP_COMMON_DIR = $(CURDIR)/../common
 BASEDIR        = ../../..
 
 # Override values given by parent make for this application as its memory usage differs from the standard app.
+# Only apply for ZPU builds - these addresses are within the ZPU's unified BRAM address space.
+# K64F uses the default heap/stack calculated by build.sh which fits within the Cortex-M4 SRAM regions.
+ifeq ($(__ZPU__),1)
 override HEAPADDR  = 0x1FFF5000
 override HEAPSIZE  = 0x00033000
 override STACKADDR = 0x20028000
 override STACKSIZE = 0x00000000
+endif
 
 # Modules making up Kilo.
 APP_C_SRC      = basic_main.c basic_editor.c basic_exectoks.c basic_expr.c basic_tokens.c basic_utils.c $(APP_COMMON_DIR)/sysutils.c