diff --git a/libopenfpga/libarchopenfpga/src/read_xml_routing_circuit.cpp b/libopenfpga/libarchopenfpga/src/read_xml_routing_circuit.cpp
index 3114276ae..5daef1310 100644
--- a/libopenfpga/libarchopenfpga/src/read_xml_routing_circuit.cpp
+++ b/libopenfpga/libarchopenfpga/src/read_xml_routing_circuit.cpp
@@ -262,7 +262,12 @@ ArchDirect read_xml_direct_circuit(pugi::xml_node& Node,
arch_direct.set_circuit_model(direct, direct_model);
/* Add more information*/
- std::string direct_type_name = get_attribute(xml_direct, "type", loc_data).as_string();
+ std::string direct_type_name = get_attribute(xml_direct, "type", loc_data, pugiutil::ReqOpt::OPTIONAL).as_string("none");
+ /* If not defined, we go to the next */
+ if (std::string("none") == direct_type_name) {
+ continue;
+ }
+
e_direct_type direct_type = string_to_direct_type(direct_type_name);
if (NUM_DIRECT_TYPES == direct_type) {
diff --git a/openfpga/test_openfpga_arch/k6_frac_N10_adder_column_chain_40nm_openfpga.xml b/openfpga/test_openfpga_arch/k6_frac_N10_adder_column_chain_40nm_openfpga.xml
new file mode 100644
index 000000000..34f44d153
--- /dev/null
+++ b/openfpga/test_openfpga_arch/k6_frac_N10_adder_column_chain_40nm_openfpga.xml
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diff --git a/openfpga/test_script/and_k6_frac_tileable_adder_column_chain.openfpga b/openfpga/test_script/and_k6_frac_tileable_adder_column_chain.openfpga
new file mode 100644
index 000000000..fbcdda185
--- /dev/null
+++ b/openfpga/test_script/and_k6_frac_tileable_adder_column_chain.openfpga
@@ -0,0 +1,62 @@
+# Run VPR for the 'and' design
+vpr ./test_vpr_arch/k6_frac_N10_tileable_adder_chain_40nm.xml ./test_blif/and.blif --route_chan_width 40 --clock_modeling route #--write_rr_graph example_rr_graph.xml
+
+# Read OpenFPGA architecture definition
+read_openfpga_arch -f ./test_openfpga_arch/k6_frac_N10_adder_column_chain_40nm_openfpga.xml
+
+# Write out the architecture XML as a proof
+#write_openfpga_arch -f ./arch_echo.xml
+
+# Annotate the OpenFPGA architecture to VPR data base
+link_openfpga_arch --activity_file ./test_blif/and.act --sort_gsb_chan_node_in_edges #--verbose
+
+# Write GSB to XML for debugging
+write_gsb_to_xml --file /var/tmp/xtang/openfpga_test_src/gsb_xml
+
+# Check and correct any naming conflicts in the BLIF netlist
+check_netlist_naming_conflict --fix --report ./netlist_renaming.xml
+
+# Apply fix-up to clustering nets based on routing results
+pb_pin_fixup --verbose
+
+# Apply fix-up to Look-Up Table truth tables based on packing results
+lut_truth_table_fixup #--verbose
+
+# Build the module graph
+# - Enabled compression on routing architecture modules
+# - Enable pin duplication on grid modules
+build_fabric --compress_routing --duplicate_grid_pin --verbose
+
+# Repack the netlist to physical pbs
+# This must be done before bitstream generator and testbench generation
+# Strongly recommend it is done after all the fix-up have been applied
+repack #--verbose
+
+# Build the bitstream
+# - Output the fabric-independent bitstream to a file
+build_architecture_bitstream --verbose --file /var/tmp/xtang/openfpga_test_src/fabric_indepenent_bitstream.xml
+
+# Build fabric-dependent bitstream
+build_fabric_bitstream --verbose
+
+# Write the Verilog netlist for FPGA fabric
+# - Enable the use of explicit port mapping in Verilog netlist
+write_fabric_verilog --file /var/tmp/xtang/openfpga_test_src/SRC --explicit_port_mapping --include_timing --include_signal_init --support_icarus_simulator --print_user_defined_template --verbose
+
+# Write the Verilog testbench for FPGA fabric
+# - We suggest the use of same output directory as fabric Verilog netlists
+# - Must specify the reference benchmark file if you want to output any testbenches
+# - Enable top-level testbench which is a full verification including programming circuit and core logic of FPGA
+# - Enable pre-configured top-level testbench which is a fast verification skipping programming phase
+# - Simulation ini file is optional and is needed only when you need to interface different HDL simulators using openfpga flow-run scripts
+write_verilog_testbench --file /var/tmp/xtang/openfpga_test_src/SRC --reference_benchmark_file_path /var/tmp/xtang/and.v --print_top_testbench --print_preconfig_top_testbench --print_simulation_ini /var/tmp/xtang/openfpga_test_src/simulation_deck.ini
+
+# Write the SDC files for PnR backend
+# - Turn on every options here
+write_pnr_sdc --file /var/tmp/xtang/openfpga_test_src/SDC
+
+# Write the SDC to run timing analysis for a mapped FPGA fabric
+write_analysis_sdc --file /var/tmp/xtang/openfpga_test_src/SDC_analysis
+
+# Finish and exit OpenFPGA
+exit