diff --git a/openfast_io/openfast_io/FAST_reader.py b/openfast_io/openfast_io/FAST_reader.py
index 4500610412..b8dbc4199d 100644
--- a/openfast_io/openfast_io/FAST_reader.py
+++ b/openfast_io/openfast_io/FAST_reader.py
@@ -1717,7 +1717,10 @@ def read_StC(self,filename):
         '''
         StC_vt = {}
 
-        with open(os.path.join(self.FAST_directory, filename)) as f:
+        # Inputs should be relative to ServoDyn, like in OpenFAST
+        SvD_dir = os.path.dirname(self.fst_vt['Fst']['ServoFile'])
+
+        with open(os.path.join(self.FAST_directory, SvD_dir, filename)) as f:
 
             f.readline()
             f.readline()
@@ -3191,7 +3194,8 @@ def read_MoorDyn(self, moordyn_file):
                     if option_name.upper() == 'WATERKIN':
                         self.fst_vt['MoorDyn']['WaterKin'] = option_value.strip('"')
                         WaterKin_file = os.path.normpath(os.path.join(os.path.dirname(moordyn_file), self.fst_vt['MoorDyn']['WaterKin']))
-                        self.read_WaterKin(WaterKin_file)
+                        if self.fst_vt['MoorDyn']['WaterKin'].upper() not in ['0','UNUSED']:
+                            self.read_WaterKin(WaterKin_file)
 
                     self.fst_vt['MoorDyn']['option_values'].append(float_read(option_value.strip('"'))) # some options values can be strings or floats
                     self.fst_vt['MoorDyn']['option_names'].append(option_name)
diff --git a/openfast_io/openfast_io/FAST_writer.py b/openfast_io/openfast_io/FAST_writer.py
index 89917a8af5..e61474d112 100644
--- a/openfast_io/openfast_io/FAST_writer.py
+++ b/openfast_io/openfast_io/FAST_writer.py
@@ -65,9 +65,9 @@ def int_default_out(val, trim = False):
     """
     if type(val) is float:
         if trim:
-            return '{:d}'.format(val)
+            return '{:d}'.format(int(val))
         else:
-            return '{:<22d}'.format(val)
+            return '{:<22d}'.format(int(val))
     else:
         if trim:
             return '{:}'.format(val)
@@ -250,7 +250,7 @@ def execute(self):
             self.write_MAP()
         elif self.fst_vt['Fst']['CompMooring'] == 3:
             self.write_MoorDyn()
-            if 'option_names' in self.fst_vt['MoorDyn'] and 'WATERKIN' in self.fst_vt['MoorDyn']['option_names']:
+            if self.fst_vt['WaterKin']:  # will be empty if not read
                 self.write_WaterKin(os.path.join(self.FAST_runDirectory,self.fst_vt['MoorDyn']['WaterKin_file']))
 
         #     # look at if the the self.fst_vt['BeamDyn'] is an array, if so, loop through the array
@@ -2497,10 +2497,14 @@ def write_MoorDyn(self):
         f.write('---------------------- SOLVER OPTIONS ---------------------------------------\n') 
         for i in range(len(self.fst_vt['MoorDyn']['option_values'])):
 
-            if 'WATERKIN' in self.fst_vt['MoorDyn']['option_names'][i]:
+            if self.fst_vt['MoorDyn']['option_names'][i].upper() == 'WATERKIN' and self.fst_vt['WaterKin']:
+                # WATERKIN needs to be a string, and should have already been read in and part of fst_vt                
                 self.fst_vt['MoorDyn']['WaterKin_file'] = self.FAST_namingOut + '_WaterKin.dat'
                 f.write('{:<22} {:<11} {:}'.format('"'+self.fst_vt['MoorDyn']['WaterKin_file']+'"', self.fst_vt['MoorDyn']['option_names'][i], self.fst_vt['MoorDyn']['option_descriptions'][i]+'\n'))
-            else: # if not waterkin handle normally
+            elif self.fst_vt['MoorDyn']['option_names'][i].upper() in ['INERTIALF','WATERKIN']:
+                # These options need to be an integer
+                f.write('{:<22} {:<11} {:}'.format(int_default_out(self.fst_vt['MoorDyn']['option_values'][i]), self.fst_vt['MoorDyn']['option_names'][i], self.fst_vt['MoorDyn']['option_descriptions'][i]+'\n'))
+            else: # if not handle normally
                 f.write('{:<22} {:<11} {:}'.format(float_default_out(self.fst_vt['MoorDyn']['option_values'][i]), self.fst_vt['MoorDyn']['option_names'][i], self.fst_vt['MoorDyn']['option_descriptions'][i]+'\n'))
 
         f.write('------------------------ OUTPUTS --------------------------------------------\n')