diff --git a/tests/export_import_pngtest.py b/tests/export_import_pngtest.py
index 5d57fdf5..57f4006d 100644
--- a/tests/export_import_pngtest.py
+++ b/tests/export_import_pngtest.py
@@ -3,13 +3,14 @@
 # Export-import test
 #
 #
-# Usage: <script> file.scad --openscad=<executable-path> --format=<format> file.png
+# Usage: <script> <inputfile> --openscad=<executable-path> --format=<format> file.png
 #
 #
-# step 1. input a .scad file, output an export format (csg, stl, off, dxf, svg, amf)
-# step 2. For non-csg exports, create a temporary new .scad file with 'import()' of exported file
-# step 3. render temporary new .scad file to .png file
-# step 4. (done in CTest) - compare the generated .png file to expected output
+# step 1. If the input file is _not_ and .scad file, create a temporary .scad file importing the input file.
+# step 2. process the .scad file, output an export format (csg, stl, off, dxf, svg, amf)
+# step 3. If the export format is _not_ .csg, create a temporary new .scad file importing the exported file
+# step 4. render the .csg or .scad file to the given .png file
+# step 5. (done in CTest) - compare the generated .png file to expected output
 #         of the original .scad file. they should be the same!
 #
 # This script should return 0 on success, not-0 on error.
@@ -24,7 +25,21 @@ def failquit(*args):
 	print('exiting test_3d_export.py with failure')
 	sys.exit(1)
 
+def createImport(inputfile, scadfile):
+        print ('createImport: ' + inputfile + " " + scadfile)
+        outputdir = os.path.dirname(scadfile)
+        try:
+                if not os.path.exists(outputdir): os.mkdir(outputdir)
+                f = open(scadfile,'w')
+                f.write('import("'+inputfile+'");'+os.linesep)
+                f.close()
+        except:
+                failquit('failure while opening/writing ' + scadfile)
+        
 
+#
+# Parse arguments
+#
 formats = ['csg', 'stl','off', 'amf', 'dxf', 'svg']
 parser = argparse.ArgumentParser()
 parser.add_argument('--openscad', required=True, help='Specify OpenSCAD executable')
@@ -32,26 +47,37 @@ parser.add_argument('--format', required=True, choices=[item for sublist in [(f,
 args,remaining_args = parser.parse_known_args()
 
 args.format = args.format.lower()
-scadfile = remaining_args[0]
+inputfile = remaining_args[0]         # Can be .scad file or a file to be imported
 pngfile = remaining_args[-1]
-remaining_args = remaining_args[1:-1]
+remaining_args = remaining_args[1:-1] # Passed on to the OpenSCAD executable
 
-if not os.path.exists(scadfile):
-	failquit('cant find .scad file named: ' + scadfile)
+if not os.path.exists(inputfile):
+	failquit('cant find input file named: ' + inputfile)
 if not os.path.exists(args.openscad):
 	failquit('cant find openscad executable named: ' + args.openscad)
 
 outputdir = os.path.dirname(pngfile)
-scadbasename = os.path.basename(scadfile)
+inputpath, inputfilename = os.path.split(inputfile)
+inputbasename,inputsuffix = os.path.splitext(inputfilename)
+
 if args.format == 'csg':
-        threedfilename = re.sub(r"\.scad$", '.' + args.format, scadfile)
+        # Must export to same folder for include/use/import to work
+        exportfile = inputfile + '.' + args.format
 else:
-        threedfilename = os.path.join(outputdir, scadbasename + '.' + args.format)
+        exportfile = os.path.join(outputdir, inputfilename)
+        if args.format != inputsuffix[1:]: exportfile += '.' + args.format
+
+# If we're not reading an .scad or .csg file, we need to import it.
+if inputsuffix != '.scad' and inputsuffix != '.csg':
+        # FIXME: Remove tempfile if created
+        tempfile = os.path.join(outputdir, inputfilename + '.scad')
+        createImport(inputfile, tempfile)
+        inputfile = tempfile
 
 #
 # First run: Just export the given filetype
 #
-export_cmd = [args.openscad, scadfile, '-o', threedfilename] + remaining_args
+export_cmd = [args.openscad, inputfile, '-o', exportfile] + remaining_args
 print('Running OpenSCAD #1:')
 print(' '.join(export_cmd))
 result = subprocess.call(export_cmd)
@@ -62,26 +88,21 @@ if result != 0:
 #
 # Second run: Import the exported file and render as png
 #
-newscadfilename = threedfilename
+newscadfile = exportfile
+# If we didn't export a .csg file, we need to import it
 if args.format != 'csg':
-        newscadfilename += '.scad'
-        try:
-                if not os.path.exists(outputdir): os.mkdir(outputdir)
-                f = open(newscadfilename,'w')
-                f.write('import("'+threedfilename+'");'+os.linesep)
-                f.close()
-        except:
-                failquit('failure while opening/writing '+newscadfilename)
+        newscadfile += '.scad'
+        createImport(exportfile, newscadfile)
 
-create_png_cmd = [args.openscad, newscadfilename, '--render', '-o', pngfile] + remaining_args
+create_png_cmd = [args.openscad, newscadfile, '--render', '-o', pngfile] + remaining_args
 print('Running OpenSCAD #2:')
 print(' '.join(create_png_cmd))
 result = subprocess.call(create_png_cmd)
 if result != 0:
 	failquit('OpenSCAD #2 failed with return code ' + str(result))
 
-try:    os.remove(threedfilename)
-except: failquit('failure at os.remove('+threedfilename+')')
-if newscadfilename != threedfilename:
-        try:	os.remove(newscadfilename)
-        except: failquit('failure at os.remove('+newscadfilename+')')
+try:    os.remove(exportfile)
+except: failquit('failure at os.remove('+exportfile+')')
+if newscadfile != exportfile:
+        try:	os.remove(newscadfile)
+        except: failquit('failure at os.remove('+newscadfile+')')