diff --git a/GUI/EvtMainFrame.cpp b/GUI/EvtMainFrame.cpp
index 48ca4c8..1bee70e 100644
--- a/GUI/EvtMainFrame.cpp
+++ b/GUI/EvtMainFrame.cpp
@@ -54,14 +54,26 @@ EvtMainFrame::EvtMainFrame(wxWindow* parent): MainFrame(parent) {
     _watcher.Connect(wxEVT_FSWATCHER, wxFileSystemWatcherEventHandler(EvtMainFrame::fileUpdateEvent), nullptr, this);
     _watcher.AddTree(wxFileName(Utility::Directory::toNativeSeparators(_manager.saveDirectory()), wxPATH_WIN),
                      wxFSW_EVENT_CREATE|wxFSW_EVENT_DELETE|wxFSW_EVENT_MODIFY|wxFSW_EVENT_RENAME, wxString::Format("*%s.sav", _manager.steamId()));
-    _watcher.AddTree(wxFileName(Utility::Directory::toNativeSeparators(_manager.stagingAreaDirectory()), wxPATH_WIN),
-                     wxFSW_EVENT_CREATE|wxFSW_EVENT_DELETE|wxFSW_EVENT_MODIFY|wxFSW_EVENT_RENAME, "*.sav");
+
+    if(_manager.hasDemoUnits()) {
+        int result = wxMessageBox("M.A.S.S.es from the demo version of the game were found.\n\n"
+                                  "Do you want to move them to the staging area ?\n"
+                                  "WARNING: M.A.S.S.es from the demo version will keep parts you haven't unlocked in the main game, so you might get an advantage if you haven't progressed to that point.",
+                                  "Question", wxCENTRE|wxYES_NO|wxICON_QUESTION, this);
+
+        if(result == wxYES) {
+            _manager.addDemoUnitsToStaging();
+        }
+    }
 
     std::vector<std::string> v = _manager.initialiseStagingArea();
     for(const std::string& s : v) {
         _stagingList->Append(s);
     }
 
+    _watcher.AddTree(wxFileName(Utility::Directory::toNativeSeparators(_manager.stagingAreaDirectory()), wxPATH_WIN),
+                     wxFSW_EVENT_CREATE|wxFSW_EVENT_DELETE|wxFSW_EVENT_MODIFY|wxFSW_EVENT_RENAME, "*.sav");
+
     _gameCheckTimer.Start(3000);
 
     if(!_manager.findScreenshotDirectory()) {
diff --git a/MassManager/MassManager.cpp b/MassManager/MassManager.cpp
index dea0e4d..cc02ec4 100644
--- a/MassManager/MassManager.cpp
+++ b/MassManager/MassManager.cpp
@@ -69,6 +69,35 @@ auto MassManager::lastError() -> std::string const& {
     return _lastError;
 }
 
+auto MassManager::hasDemoUnits() -> bool {
+    using Utility::Directory::Flag;
+    std::vector<std::string> list = Utility::Directory::list(_saveDirectory, Flag::SkipSpecial|Flag::SkipDirectories|Flag::SkipDotAndDotDot);
+
+    for(const std::string& file : list) {
+        if(Utility::String::beginsWith(file, "DemoUnit") && Utility::String::endsWith(file, ".sav")) {
+            return true;
+        }
+    }
+
+    return false;
+}
+
+void MassManager::addDemoUnitsToStaging() {
+    using Utility::Directory::Flag;
+    std::vector<std::string> list = Utility::Directory::list(_saveDirectory, Flag::SkipSpecial|Flag::SkipDirectories|Flag::SkipDotAndDotDot);
+
+    auto predicate = [](const std::string& name)->bool{
+        return !(Utility::String::endsWith(name, ".sav") && Utility::String::beginsWith(name, "DemoUnit"));
+    };
+
+    list.erase(std::remove_if(list.begin(), list.end(), predicate), list.end());
+
+    for(const std::string& file : list) {
+        Utility::Directory::move(Utility::Directory::join(_saveDirectory, file),
+                                 Utility::Directory::join(_stagingAreaDirectory, file));
+    }
+}
+
 auto MassManager::saveDirectory() -> std::string const& {
     return _saveDirectory;
 }
diff --git a/MassManager/MassManager.h b/MassManager/MassManager.h
index e1b3b34..1c610b4 100644
--- a/MassManager/MassManager.h
+++ b/MassManager/MassManager.h
@@ -58,6 +58,9 @@ class MassManager {
         auto ready() -> bool;
         auto lastError() -> std::string const&;
 
+        auto hasDemoUnits() -> bool;
+        void addDemoUnitsToStaging();
+
         auto saveDirectory() -> std::string const&;
         auto stagingAreaDirectory() -> std::string const&;
         auto screenshotDirectory() -> std::string const&;