diff --git a/flopy/export/netcdf.py b/flopy/export/netcdf.py
index 3b29125b2d..00e9e583bf 100644
--- a/flopy/export/netcdf.py
+++ b/flopy/export/netcdf.py
@@ -219,7 +219,7 @@ def __init__(
         self.global_attributes = {}
         self.global_attributes["namefile"] = self.model.namefile
         self.global_attributes["model_ws"] = self.model.model_ws
-        self.global_attributes["exe_name"] = self.model.exe_name
+        self.global_attributes["exe_name"] = self.model.exename
         self.global_attributes["modflow_version"] = self.model.version
 
         self.global_attributes["create_hostname"] = socket.gethostname()
diff --git a/flopy/export/utils.py b/flopy/export/utils.py
index a40af73b90..e490c6ea7a 100644
--- a/flopy/export/utils.py
+++ b/flopy/export/utils.py
@@ -1026,7 +1026,16 @@ def transient2d_export(f: Union[str, os.PathLike], t2d, fmt=None, **kwargs):
 
         array = t2d.array
         with np.errstate(invalid="ignore"):
-            if array.dtype not in [int, np.int32, np.int64]:
+            from numpy import dtype
+
+            if array.dtype not in [
+                int,
+                np.int32,
+                np.int64,
+                dtype("float64"),
+                dtype("int64"),
+                dtype("int32"),
+            ]:
                 if mask is not None:
                     array[:, 0, mask] = np.nan
                 array[array <= min_valid] = np.nan
diff --git a/flopy/mbase.py b/flopy/mbase.py
index 40cdbf700f..3eff8fb836 100644
--- a/flopy/mbase.py
+++ b/flopy/mbase.py
@@ -165,6 +165,13 @@ def update_modelgrid(self):
             )
         self._mg_resync = True
 
+    @property
+    @abc.abstractmethod
+    def modeltime(self):
+        raise NotImplementedError(
+            "must define modeltime in child class to use this base class"
+        )
+
     @property
     @abc.abstractmethod
     def modelgrid(self):
diff --git a/flopy/modflow/mf.py b/flopy/modflow/mf.py
index a5394d3e69..7ce4ca18b5 100644
--- a/flopy/modflow/mf.py
+++ b/flopy/modflow/mf.py
@@ -140,6 +140,8 @@ def __init__(
         if self.version == "mf2k":
             self.glo = ModflowGlobal(self)
 
+        self._exename = exe_name
+
         self.lst = ModflowList(self, unitnumber=listunit)
         # -- check if unstructured is specified for something
         # other than mfusg is specified