diff --git a/custom_field_list.json b/custom_field_list.json
index 098dfb7..cc13499 100644
--- a/custom_field_list.json
+++ b/custom_field_list.json
@@ -19,17 +19,13 @@
     ]
 },
 "4FSKTEST-V2": {
-    "struct": "<BBBBBBBBB",
+    "struct": "<BfBBH",
     "fields": [
         ["test_field 1", "none"],
         ["test_field 2", "none"],
-        ["test_field 3", "none"],
-        ["test_field 4", "none"],
-        ["test_field 5", "none"],
-        ["test_field 6", "none"],
-        ["test_field 7", "none"],
-        ["test_field 8", "none"],
-        ["test_field 9", "none"]
+        ["test_field 3", "battery_5v_byte"],
+        ["test_field 4", "divide_by_10"],
+        ["test_field 5", "divide_by_100"]
     ]
 }
 }
\ No newline at end of file
diff --git a/horusdemodlib/__init__.py b/horusdemodlib/__init__.py
index b5fdc75..d31c31e 100755
--- a/horusdemodlib/__init__.py
+++ b/horusdemodlib/__init__.py
@@ -1 +1 @@
-__version__ = "0.2.2"
+__version__ = "0.2.3"
diff --git a/horusdemodlib/delegates.py b/horusdemodlib/delegates.py
index 8b5d900..62d7604 100644
--- a/horusdemodlib/delegates.py
+++ b/horusdemodlib/delegates.py
@@ -141,13 +141,39 @@ def decode_battery_5v_byte(data: int) -> str:
     return (_batt, f"{_batt:.2f}")
 
 
+def decode_divide_by_10(data: int) -> str:
+    """
+    Accepts an fixed-point integer, and returns it as its value divided by 10, as a string.
+    """
+    if type(data) != int:
+        raise ValueError("divide_by_10 - Invalid input type")
+    
+    _val = data/10.0
+
+    return (_val, f"{_val:.1f}")
+
+
+def decode_divide_by_100(data: int) -> str:
+    """
+    Accepts an fixed-point integer, and returns it as its value divided by 100, as a string.
+    """
+    if type(data) != int:
+        raise ValueError("divide_by_100 - Invalid input type")
+    
+    _val = data/100.0
+
+    return (_val, f"{_val:.2f}")
+
+
 delegate_list = {
     'payload_id': decode_payload_id,
     'time_hms': decode_time_hms,
     'time_biseconds': decode_time_biseconds,
     'degree_float': decode_degree_float,
     'degree_fixed3': decode_degree_fixed3,
-    'battery_5v_byte': decode_battery_5v_byte
+    'battery_5v_byte': decode_battery_5v_byte,
+    'divide_by_10': decode_divide_by_10,
+    'divide_by_100': decode_divide_by_100,
 }
 
 def decode_field(field_type:str, data):
@@ -158,7 +184,9 @@ def decode_field(field_type:str, data):
     else:
         if (field_type == 'none') or (field_type == 'None') or (field_type == None):
             # Basic datatype, just convert to a string using Pythons internal conversions.
-            if (type(data) == float) or (type(data) == int) or (type(data) == str):
+            if (type(data) == float):
+                return (data, f"{data:.6f}")
+            elif (type(data) == int) or (type(data) == str):
                 return (data, f"{data}")
             else:
                 raise ValueError(f"Data has unknown type ({str(type(data))}) and could not be decoded.")
@@ -227,7 +255,12 @@ if __name__ == "__main__":
         ['battery_5v_byte', 0, "0.00"],
         ['battery_5v_byte', 128, "2.51"],
         ['battery_5v_byte', 255, "5.00"],
-        ['payload_id', 0, '4FSKTEST']
+        ['payload_id', 0, '4FSKTEST'],
+        ['divide_by_10', 123, "12.3"],
+        ['divide_by_10', -456, "-45.6"],
+        ['divide_by_100', 123, "1.23"],
+        ['divide_by_100', -456, "-4.56"],
+
     ]
 
     for _test in tests:
diff --git a/horusdemodlib/payloads.py b/horusdemodlib/payloads.py
index c0f86f0..de7385e 100644
--- a/horusdemodlib/payloads.py
+++ b/horusdemodlib/payloads.py
@@ -4,6 +4,7 @@
 import json
 import logging
 import requests
+import struct
 
 # Global payload list - Basic version
 HORUS_PAYLOAD_LIST = {0:'4FSKTEST', 1:'HORUSBINARY', 257:'4FSKTEST32', 65535:'HORUSTEST'}
@@ -12,6 +13,7 @@ HORUS_PAYLOAD_LIST = {0:'4FSKTEST', 1:'HORUSBINARY', 257:'4FSKTEST32', 65535:'HO
 PAYLOAD_ID_LIST_URL = "https://raw.githubusercontent.com/projecthorus/horusdemodlib/master/payload_id_list.txt"
 
 # Custom field data. 
+HORUS_CUSTOM_FIELD_LENGTH = 9
 HORUS_CUSTOM_FIELDS = {
     "HORUSTEST": {
         "struct": "<BbBfH",
@@ -191,11 +193,21 @@ def read_custom_field_list(filename="custom_field_list.json"):
             _data = _field_data[_payload]
 
             if ("struct" in _data) and ("fields" in _data):
-                _custom_field_list[_payload] = {
-                    "struct": _data["struct"],
-                    "fields": _data["fields"]
-                }
-                logging.debug(f"Loaded custom field data for {_payload}.")
+                # Check the struct value has the right length
+                try:
+                    _structsize = struct.calcsize(_data["struct"])
+
+                    if _structsize == HORUS_CUSTOM_FIELD_LENGTH:
+                        _custom_field_list[_payload] = {
+                            "struct": _data["struct"],
+                            "fields": _data["fields"]
+                        }
+                        logging.debug(f"Loaded custom field data for {_payload}.")
+                    else:
+                        logging.error(f"Struct field for {_payload} has incorrect length ({_structsize}).")
+                        
+                except Exception as e:
+                    logging.error(f"Could not parse custom field data for {_payload}: {str(e)}")
         
         return _custom_field_list
 
@@ -264,11 +276,23 @@ def download_latest_custom_field_list(url=HORUS_CUSTOM_FIELD_URL, filename=None,
             _data = _field_data[_payload]
 
             if ("struct" in _data) and ("fields" in _data):
-                _custom_field_list[_payload] = {
-                    "struct": _data["struct"],
-                    "fields": _data["fields"]
-                }
-                logging.debug(f"Loaded custom field data for {_payload}.")
+                # Check the struct value has the right length
+                try:
+                    _structsize = struct.calcsize(_data["struct"])
+
+                    if _structsize == HORUS_CUSTOM_FIELD_LENGTH:
+                        _custom_field_list[_payload] = {
+                            "struct": _data["struct"],
+                            "fields": _data["fields"]
+                        }
+                        logging.debug(f"Loaded custom field data for {_payload}.")
+                    else:
+                        logging.error(f"Struct field for {_payload} has incorrect length ({_structsize}).")
+
+                except Exception as e:
+                    logging.error(f"Could not parse custom field data for {_payload}: {str(e)}")
+
+
 
     except Exception as e:
         logging.error(f"Could not parse downloaded custom field list - {str(e)}")
diff --git a/src/horus_gen_test_bits.c b/src/horus_gen_test_bits.c
index 50de9ae..a2d2b10 100644
--- a/src/horus_gen_test_bits.c
+++ b/src/horus_gen_test_bits.c
@@ -58,14 +58,10 @@ struct TBinaryPacket1
     int8_t      Temp;        // Twos Complement Temp value.
     uint8_t     BattVoltage; // 0 = 0.5v, 255 = 2.0V, linear steps in-between.
     uint8_t     dummy1;      // Dummy values for user-configurable section.
-    uint8_t     dummy2;
-    uint8_t     dummy3;
-    uint8_t     dummy4;
-    uint8_t     dummy5;
-    uint8_t     dummy6;
-    uint8_t     dummy7;
-    uint8_t     dummy8;
-    uint8_t     dummy9;
+    float     dummy2;       // Float 
+    uint8_t     dummy3;     // battery voltage test
+    uint8_t     dummy4;     // divide by 10
+    uint16_t     dummy5;    // divide by 100
     uint16_t    Checksum;    // CRC16-CCITT Checksum.
 }  __attribute__ ((packed));
 
@@ -150,14 +146,10 @@ int main(int argc,char *argv[]) {
         input_payload.Minutes = 34;
         input_payload.Seconds = 56;
         input_payload.dummy1 = 1;
-        input_payload.dummy2 = 2;
-        input_payload.dummy3 = 3;
-        input_payload.dummy4 = 4;
-        input_payload.dummy5 = 5;
-        input_payload.dummy6 = 6;
-        input_payload.dummy7 = 7;
-        input_payload.dummy8 = 8;
-        input_payload.dummy9 = 9;
+        input_payload.dummy2 = 1.23456789;
+        input_payload.dummy3 = 200;
+        input_payload.dummy4 = 123;
+        input_payload.dummy5 = 1234;
         input_payload.Counter = counter;
         input_payload.Checksum = horus_l2_gen_crc16((unsigned char*)&input_payload, nbytes-2);