Hi Jeff,
I have not yet checked my Regexp question type against current Moodle 1.7 stable but will do so shortly. If you have only dumped the regexp folder inside your moodle 1.7 \question\type folder and not changed the \question\format\xml\format.php file, it is "normal" that you cannot export/import the regexp questions you created.
As far as I can see, all you have to do for the import/export of regexp to work is to uncomment all the lines concerning this question type in file \question\format\xml\format.php.
Joseph
PS.- Use at own risk and not on a production server but on a test server...

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