diff -ur openshot-1.4.0-orig/openshot/classes/cli_render.py openshot-1.4.0/openshot/classes/cli_render.py
--- openshot-1.4.0-orig/openshot/classes/cli_render.py	2011-12-04 20:36:06.000000000 +0400
+++ openshot-1.4.0/openshot/classes/cli_render.py	2011-12-04 20:50:20.000000000 +0400
@@ -265,6 +265,9 @@
 		# Create producer and initialize mlt
 		self.f = mlt.Factory().init()
 		self.p = mlt.Producer( self.profile, 'xml:%s' % self.file_name)
+		if self.p.is_valid() == False:
+			print _("MLT producer failure")
+			sys.exit()
 		self.p.set_speed(0)
 		out_folder = self.render_options["folder"]
 		out_file = self.render_options["file"]
diff -ur openshot-1.4.0-orig/openshot/classes/thumbnail.py openshot-1.4.0/openshot/classes/thumbnail.py
--- openshot-1.4.0-orig/openshot/classes/thumbnail.py	2011-12-04 20:36:06.000000000 +0400
+++ openshot-1.4.0/openshot/classes/thumbnail.py	2011-12-04 20:40:13.000000000 +0400
@@ -176,7 +176,11 @@
 				# mark as image seq
 				self.label = "Image Sequence"
 				self.file_type = "image sequence"
-			
+
+			# Check if clip is valid (otherwise a seg fault)
+			if self.p.is_valid() == False:
+				return None
+
 			# connect the producer and consumer
 			self.c.connect( self.p )
 
@@ -284,6 +288,10 @@
 		
 		#get the frame
 		self.p = self.p.cut(frame, frame)
+
+		# Check if clip is valid (otherwise a seg fault)
+		if self.p.is_valid() == False:
+			return None
 		
 		# connect the producer and consumer
 		self.c.connect( self.p )
diff -ur openshot-1.4.0-orig/openshot/classes/video.py openshot-1.4.0/openshot/classes/video.py
--- openshot-1.4.0-orig/openshot/classes/video.py	2011-12-04 20:36:06.000000000 +0400
+++ openshot-1.4.0/openshot/classes/video.py	2011-12-04 21:06:31.000000000 +0400
@@ -114,6 +114,9 @@
 	
 			# Create the producer
 			self.p = mlt.Producer( self.profile, 'xml:%s' % self.file_name)
+			if self.p.is_valid() == False:
+				print "ERROR WITH %s" % self.file_name
+				return
 
 			# get export file path
 			folder = self.render_options["folder"]
@@ -171,6 +174,9 @@
 			
 			# Create the producer
 			self.p = mlt.Producer( self.profile, 'xml:%s' % self.file_name)
+			if self.p.is_valid() == False:
+				print "ERROR WITH %s" % self.file_name
+				return
 
 			# refresh sdl and pause video
 			self.pause()