There are some settings you can adjust to make the File Manager more stable and potentially faster.
Make sure any/all extra applications on the remote and local PCs are closed down during the session.
You can toggle the compression settings within LogMeIn. Go to Preferences > Network Settings. Adaptive, No, Fast, Low, Normal and Best are the options for file transfer compression. Typically, Adaptive is the default, but you should see different results with different selections on your system. Click Apply with any changes made.