diff --git a/toonz/sources/common/tunit/tunit.cpp b/toonz/sources/common/tunit/tunit.cpp
index 90bbf63..6609619 100644
--- a/toonz/sources/common/tunit/tunit.cpp
+++ b/toonz/sources/common/tunit/tunit.cpp
@@ -457,7 +457,7 @@ void TMeasuredValue::setMeasure(std::string measureName) {
 //-------------------------------------------------------------------
 
 bool TMeasuredValue::setValue(std::wstring s, int *pErr) {
-  if (s == L"") {
+  if (s == L"" || s == L"-") {
     if (pErr) *pErr = -1;
     return false;
   }
diff --git a/toonz/sources/tnztools/tooloptions.cpp b/toonz/sources/tnztools/tooloptions.cpp
index b6f058b..e905522 100644
--- a/toonz/sources/tnztools/tooloptions.cpp
+++ b/toonz/sources/tnztools/tooloptions.cpp
@@ -1663,7 +1663,7 @@ void FillToolOptionsBox::updateStatus() {
 void FillToolOptionsBox::onColorModeChanged() {
   bool enabled = m_colorMode->currentText() != QString("Lines");
   m_selectiveMode->setEnabled(enabled);
-  m_autopaintMode->setEnabled(enabled);
+  if(m_autopaintMode) m_autopaintMode->setEnabled(enabled);
   if (m_fillDepthLabel && m_fillDepthField) {
     m_fillDepthLabel->setEnabled(enabled);
     m_fillDepthField->setEnabled(enabled);