Ok, I tested with:
Version 1.80RC1 (5885), and
Version 1.80RC2 (6082)
I have the same behavior. The e-mail invitation is sent normally but the e-mail reminder does not work.
I am uploading the test survey I used. I changed the extension from csv to txt so I can upload the file.
I am using:
Allow saves: NO
Show [<< Prev] button : YES
Participants may print answers? : YES
Use HTML format for token emails?: NO
Use cookies? : NO
Anonymous answers? : NO
Enable Token-based answers persistence?: YES
Now, the difference is: Use HTML format for token emails?
With NO HTML format the reminder does NOT work. If I select to use HTML format then it works.
I need the HTML format to NO to append:
{SURVEYURL}&newtest=Y
which fixed a bug with the token persistence.
Please let me know if you need more info...