diff --git a/rostests/apitests/gdi32api/testlist.c b/rostests/apitests/gdi32api/testlist.c
index a21e9d2ff42..a68d6d304c0 100644
--- a/rostests/apitests/gdi32api/testlist.c
+++ b/rostests/apitests/gdi32api/testlist.c
@@ -18,7 +18,7 @@
 #include "tests/SelectObject.c"
 #include "tests/SetDCPenColor.c"
 #include "tests/SetSysColors.c"
-//#include "tests/SetWorldTransform.c"
+#include "tests/SetWorldTransform.c"
 
 /* The List of tests */
 TESTENTRY TestList[] =
@@ -37,7 +37,7 @@ TESTENTRY TestList[] =
 	{ L"SetSysColors", Test_SetSysColors },
 	{ L"SelectObject", Test_SelectObject },
 	{ L"SetDCPenColor", Test_SetDCPenColor },
-//	{ L"SetWorldTransform", Test_SetWorldTransform },
+	{ L"SetWorldTransform", Test_SetWorldTransform },
 };
 
 /* The function that gives us the number of tests */
diff --git a/rostests/apitests/gdi32api/tests/CreateCompatibleDC.c b/rostests/apitests/gdi32api/tests/CreateCompatibleDC.c
index f31103d567c..17337bd9da3 100644
--- a/rostests/apitests/gdi32api/tests/CreateCompatibleDC.c
+++ b/rostests/apitests/gdi32api/tests/CreateCompatibleDC.c
@@ -3,12 +3,23 @@ Test_CreateCompatibleDC(PTESTINFO pti)
 {
 	HDC hDCScreen, hOldDC, hDC, hDC2;
 
-	// Create a DC
+	/* Get screen DC */
 	hDCScreen = GetDC(NULL);
-	if (hDCScreen == NULL)
-	{
-		return FALSE;
-	}
+	ASSERT(hDCScreen != NULL);
+
+	/* Test NULL DC handle */
+	SetLastError(ERROR_SUCCESS);
+	hDC = CreateCompatibleDC(NULL);
+	TEST(hDC != NULL);
+	TEST(GetLastError() == ERROR_SUCCESS);
+	if(hDC) DeleteDC(hDC);
+
+	/* Test invalid DC handle */
+	SetLastError(ERROR_SUCCESS);
+	hDC = CreateCompatibleDC((HDC)0x123456);
+	TEST(hDC == NULL);
+	TEST(GetLastError() == ERROR_SUCCESS);
+	if(hDC) DeleteDC(hDC);
 
 	hDC = CreateCompatibleDC(hDCScreen);
 	RTEST(hDC != NULL);
diff --git a/rostests/apitests/gdi32api/tests/GetClipRgn.c b/rostests/apitests/gdi32api/tests/GetClipRgn.c
index 14bd2a87776..fee7b051d85 100644
--- a/rostests/apitests/gdi32api/tests/GetClipRgn.c
+++ b/rostests/apitests/gdi32api/tests/GetClipRgn.c
@@ -13,8 +13,15 @@ Test_GetClipRgn(PTESTINFO pti)
 	hDC = GetDC(hWnd);
 	hrgn = CreateRectRgn(0,0,0,0);
 
+	/* Test invalid DC */
 	SetLastError(ERROR_SUCCESS);
-//	TEST(GetClipRgn(hDC)
+	TEST(GetClipRgn((HDC)0x12345, hrgn) == -1);
+	TEST(GetLastError() == ERROR_INVALID_PARAMETER);
+
+	/* Test invalid hrgn */
+	SetLastError(ERROR_SUCCESS);
+	TEST(GetClipRgn(hDC, (HRGN)0x12345) == 0);
+	TEST(GetLastError() == ERROR_SUCCESS);
 
 	ReleaseDC(hWnd, hDC);
 	DestroyWindow(hWnd);
diff --git a/rostests/apitests/gdi32api/tests/SelectObject.c b/rostests/apitests/gdi32api/tests/SelectObject.c
index 5e0a6a880cb..c45b318b1f6 100644
--- a/rostests/apitests/gdi32api/tests/SelectObject.c
+++ b/rostests/apitests/gdi32api/tests/SelectObject.c
@@ -2,7 +2,7 @@ INT
 Test_SelectObject(PTESTINFO pti)
 {
 	HGDIOBJ hOldObj, hNewObj;
-	HDC hScreenDC, hDC;
+	HDC hScreenDC, hDC, hDC2;
 	PGDI_TABLE_ENTRY pEntry;
 	PDC_ATTR pDc_Attr;
 	HANDLE hcmXform;
@@ -35,6 +35,16 @@ Test_SelectObject(PTESTINFO pti)
 	TEST(pDc_Attr->hbrush == hNewObj);
 	SelectObject(hDC, hOldObj);
 
+	/* Test wrong hDC handle type */
+	SetLastError(ERROR_SUCCESS);
+	hNewObj = GetStockObject(GRAY_BRUSH);
+	hDC2 = (HDC)((UINT_PTR)hDC & ~GDI_HANDLE_TYPE_MASK);
+	hDC2 = (HDC)((UINT_PTR)hDC2 | GDI_OBJECT_TYPE_PEN);
+	hOldObj = SelectObject(hDC2, hNewObj);
+	TEST(GetLastError() == ERROR_INVALID_HANDLE);
+	TEST(hOldObj == NULL);
+	TEST(pDc_Attr->hbrush == GetStockObject(WHITE_BRUSH));
+
 	/* Test wrong hobj handle type */
 	SetLastError(ERROR_SUCCESS);
 	hNewObj = GetStockObject(GRAY_BRUSH);
diff --git a/rostests/apitests/gdi32api/tests/SetDCPenColor.c b/rostests/apitests/gdi32api/tests/SetDCPenColor.c
index b04bb936d0c..225379c0bce 100644
--- a/rostests/apitests/gdi32api/tests/SetDCPenColor.c
+++ b/rostests/apitests/gdi32api/tests/SetDCPenColor.c
@@ -4,7 +4,9 @@ Test_SetDCPenColor(PTESTINFO pti)
 	HDC hScreenDC, hDC;
 
 	// Test an incorrect DC
+	SetLastError(ERROR_SUCCESS);
 	RTEST(SetDCPenColor(0, RGB(0,0,0)) == CLR_INVALID);
+	TEST(GetLastError() == ERROR_INVALID_PARAMETER);
 
 	// Get the Screen DC
 	hScreenDC = GetDC(NULL);
diff --git a/rostests/apitests/gdi32api/tests/SetWorldTransform.c b/rostests/apitests/gdi32api/tests/SetWorldTransform.c
new file mode 100644
index 00000000000..7aa79d5cdea
--- /dev/null
+++ b/rostests/apitests/gdi32api/tests/SetWorldTransform.c
@@ -0,0 +1,20 @@
+INT
+Test_SetWorldTransform(PTESTINFO pti)
+{
+	PGDI_TABLE_ENTRY pEntry;
+	HDC hScreenDC, hDC;
+	DC_ATTR* pDC_Attr;
+
+	/* Create a DC */
+	hScreenDC = GetDC(NULL);
+	hDC = CreateCompatibleDC(hScreenDC);
+	ReleaseDC(NULL, hScreenDC);
+	SetGraphicsMode(hDC, GM_ADVANCED);
+
+	pEntry = GdiHandleTable + GDI_HANDLE_GET_INDEX(hDC);
+	pDC_Attr = pEntry->UserData;
+
+	DeleteDC(hDC);
+
+	return APISTATUS_NORMAL;
+}