diff --git a/src/common/kernel/battle.c b/src/common/kernel/battle.c
index 022a79abc..757ba936e 100644
--- a/src/common/kernel/battle.c
+++ b/src/common/kernel/battle.c
@@ -1872,7 +1872,6 @@ do_extra_spell(troop at, const att *a)
 {
   const spell *sp = a->data.sp;
   fighter *fi = at.fighter;
-  unit *au = fi->unit;
   double power;
 
   power = sp->level * MagicPower();
diff --git a/src/common/kernel/plane.c b/src/common/kernel/plane.c
index c2ec54337..770e90558 100644
--- a/src/common/kernel/plane.c
+++ b/src/common/kernel/plane.c
@@ -93,7 +93,7 @@ getplanebyname(const char * name)
   plane *p;
 
   for (p=planes; p; p=p->next)
-    if (!strcmp(p->name, name))
+    if (p->name && !strcmp(p->name, name))
       return p;
   return NULL;
 }
diff --git a/src/common/kernel/race.c b/src/common/kernel/race.c
index dce50a583..a736e59b7 100644
--- a/src/common/kernel/race.c
+++ b/src/common/kernel/race.c
@@ -204,7 +204,7 @@ r_insectstalled(const region * r)
 const char *
 rc_name(const race * rc, int n)
 {
-  return mkname("race", rc->_name[n]);
+  return rc?mkname("race", rc->_name[n]):NULL;
 }
 
 const char *
diff --git a/src/common/kernel/reports.c b/src/common/kernel/reports.c
index 073745998..718cb134f 100644
--- a/src/common/kernel/reports.c
+++ b/src/common/kernel/reports.c
@@ -303,7 +303,7 @@ report_race(const struct unit * u, const char ** name, const char ** illusion)
 {
   if (illusion) {
     const race * irace = u_irace(u);
-    if (irace!=u->race) {
+    if (irace && irace!=u->race) {
       *illusion = irace->_name[0];
     }
     else {
diff --git a/src/common/kernel/save.c b/src/common/kernel/save.c
index c450d00c3..b8793e57f 100644
--- a/src/common/kernel/save.c
+++ b/src/common/kernel/save.c
@@ -853,7 +853,7 @@ write_unit(struct storage * store, const unit * u)
   store->w_int(store, u->number);
   store->w_int(store, u->age);
   store->w_tok(store, u->race->_name[0]);
-  store->w_tok(store, irace!=u->race?u->irace->_name[0]:"");
+  store->w_tok(store, (irace && irace!=u->race)?irace->_name[0]:"");
   write_building_reference(u->building, store);
   write_ship_reference(u->ship, store);
   store->w_int(store, u->status);
diff --git a/src/common/kernel/unit.c b/src/common/kernel/unit.c
index 91e6533fc..66c3fe3b3 100644
--- a/src/common/kernel/unit.c
+++ b/src/common/kernel/unit.c
@@ -1733,8 +1733,8 @@ scale_number (unit * u, int n)
 
 const struct race * u_irace(const struct unit * u)
 {
-  if (skill_enabled[SK_STEALTH]) {
+  if (u->irace && skill_enabled[SK_STEALTH]) {
     return u->irace;
   }
   return u->race;
-}
\ No newline at end of file
+}
diff --git a/src/eressea/tolua/bind_building.c b/src/eressea/tolua/bind_building.c
index 3f3666925..8abc8a75c 100644
--- a/src/eressea/tolua/bind_building.c
+++ b/src/eressea/tolua/bind_building.c
@@ -164,9 +164,11 @@ tolua_building_create(lua_State* L)
   const char * bname = tolua_tostring(L, 2, 0);
   if (bname) {
     const building_type * btype = bt_find(bname);
-    building * b = new_building(btype, r, NULL);
-    tolua_pushusertype(L, (void*)b, TOLUA_CAST "building");
-    return 1;
+    if (btype) {
+      building * b = new_building(btype, r, NULL);
+      tolua_pushusertype(L, (void*)b, TOLUA_CAST "building");
+      return 1;
+    }
   }
   return 0;
 }
diff --git a/src/eressea/tolua/bind_unit.c b/src/eressea/tolua/bind_unit.c
index 616b6a21f..562b2d2e3 100644
--- a/src/eressea/tolua/bind_unit.c
+++ b/src/eressea/tolua/bind_unit.c
@@ -664,7 +664,7 @@ static void
 unit_setship(unit * u, ship * s)
 {
   leave(u, true);
-  if (u->region!=s->region) {
+  if (s && u->region!=s->region) {
     move_unit(u, s->region, NULL);
   }
   u->ship = s;
diff --git a/src/scripts/config-test.lua b/src/scripts/config-test.lua
new file mode 100644
index 000000000..67bb64082
--- /dev/null
+++ b/src/scripts/config-test.lua
@@ -0,0 +1 @@
+maxnmrs = 500
diff --git a/src/scripts/tests.lua b/src/scripts/tests.lua
index b97972169..d73d14906 100644
--- a/src/scripts/tests.lua
+++ b/src/scripts/tests.lua
@@ -625,12 +625,13 @@ function test_leave()
   b2.size = 10
   local u = unit.create(f, r, 1)
   u.building = b1
+  assert(u.building~=nil)
   u:add_item("money", u.number * 100)
   u:clear_orders()
   u:add_order("BETRETE BURG " .. itoa36(b2.id))
   update_owners()
   process_orders()
-  assert(u.building==b1)
+  assert(u.building.id==b1.id) -- region owners may not leave
 end
 
 function test_mallorn()
@@ -787,7 +788,7 @@ mytests = {
     ["owners"] = test_owners
 }
 fail = 0
-for k, v in pairs(mytests) do
+for k, v in pairs(tests) do
     local status, err = pcall(v)
     if not status then
         fail = fail + 1