diff --git a/src/slic3r.cpp b/src/slic3r.cpp
index 3df317196..27c64000b 100644
--- a/src/slic3r.cpp
+++ b/src/slic3r.cpp
@@ -36,7 +36,6 @@ int CLI::run(int argc, char **argv) {
     // Convert arguments to UTF-8 (needed on Windows).
     // argv then points to memory owned by a.
     boost::nowide::args a(argc, argv);
-    std::cerr<<"after boost::nowide<<args"<<std::endl;
     // parse all command line options into a DynamicConfig
     t_config_option_keys opt_order;
     this->config_def.merge(cli_actions_config_def);
@@ -44,7 +43,7 @@ int CLI::run(int argc, char **argv) {
     this->config_def.merge(cli_misc_config_def);
     this->config_def.merge(print_config_def);
     this->config.def = &this->config_def;
-    std::cerr<<"after merges"<<std::endl;
+    std::cerr<<"Configs merged"<<std::endl;
     // if any option is unsupported, print usage and abort immediately
     if (!this->config.read_cli(argc, argv, &this->input_files, &opt_order)) {
         this->print_help();
@@ -85,10 +84,10 @@ int CLI::run(int argc, char **argv) {
     // (command line options override --load files)
     this->print_config.apply(config, true);
     this->print_config.normalize();
-    std::cerr<<"after config normalize" << std::endl;
+    std::cerr<<"Print_config normalized" << std::endl;
     // create a static (full) print config to be used in our logic
     this->full_print_config.apply(this->print_config);
-    std::cerr<<"apply full config"<<std::endl;
+    std::cerr<<"Full_print_config created"<<std::endl;
     // validate config
     try {
         this->full_print_config.validate();
@@ -96,7 +95,7 @@ int CLI::run(int argc, char **argv) {
         boost::nowide::cerr << e.what() << std::endl;
         return 1;
     }
-    std::cerr<<"after config validation"<<std::endl;
+    std::cerr<<"Config validated"<<std::endl;
     
     // read input file(s) if any
     for (auto const &file : input_files) {
@@ -326,6 +325,7 @@ int CLI::run(int argc, char **argv) {
                 print.center = !this->config.has("center")
                     && !this->config.has("align_xy")
                     && !this->config.getBool("dont_arrange");
+                std::cerr<<"Arrange: "<<print.arrange<<", center: "<<print.center<<std::endl;
                 print.set_model(model);
                 
                 // start chronometer
diff --git a/xs/src/libslic3r/ConfigBase.cpp b/xs/src/libslic3r/ConfigBase.cpp
index 4ff569ca0..44655873f 100644
--- a/xs/src/libslic3r/ConfigBase.cpp
+++ b/xs/src/libslic3r/ConfigBase.cpp
@@ -928,7 +928,7 @@ ConfigOptionPoint::deserialize(std::string str, bool append) {
         this->value.x = boost::lexical_cast<coordf_t>(tokens[0]);
         this->value.y = boost::lexical_cast<coordf_t>(tokens[1]);
     } catch (boost::bad_lexical_cast &e){
-        std::cout << "Exception caught : " << e.what() << std::endl;
+        std::cout << "Config option deserialisation error of ["<<str<<"]  : " << e.what()<<" (expected 2D point)" << std::endl;
         return false;
     }
     return true;
@@ -943,7 +943,7 @@ ConfigOptionPoint3::deserialize(std::string str, bool append) {
         this->value.y = boost::lexical_cast<coordf_t>(tokens[1]);
         this->value.z = boost::lexical_cast<coordf_t>(tokens[2]);
     } catch (boost::bad_lexical_cast &e){
-        std::cout << "Exception caught : " << e.what() << std::endl;
+        std::cout << "Config option deserialisation error of ["<<str<<"]  : " << e.what()<<" (expected 3D point)" << std::endl;
         return false;
     }
     return true;
diff --git a/xs/src/libslic3r/SupportMaterial.cpp b/xs/src/libslic3r/SupportMaterial.cpp
index 19dd54edf..9c3912f76 100644
--- a/xs/src/libslic3r/SupportMaterial.cpp
+++ b/xs/src/libslic3r/SupportMaterial.cpp
@@ -70,8 +70,10 @@ SupportMaterial::generate(PrintObject *object)
     map<coordf_t, Polygons> &overhang = contact_overhang.second;
 
     //bugfix: do not try to generate overhang if there is no contact area 
-    if( contact.empty() )
-	return;
+    if( contact.empty() ){
+	std::cerr<<"Empty contact_areas of SupportMaterial for object ["<<object->model_object()->name<<"]"<<std::endl;
+    	return;
+    }
 	
     // Determine the top surfaces of the object. We need these to determine
     // the layer heights of support material and to clip support to the object