Sorry I didn't get to this sooner, newcom1 - been a bit swamped with work, as of late.
Took a look at the code indicated by your error, and I have to admit, I'm at a bit of a loss. There appears to be no apparent reason you'd get that type of error in that function. Not to say it couldn't happen - it apparently did D:
If you happen to still have the plugin installed, could you check to confirm that the function get_bases is on line 759, and maybe do a print_r on $this->_rewrites, see what it spits out?
To trigger that function, you'll need to hit 'save' on the permalinks page, seeing as you can't get to the options page for this plugin
Speaking of which, this has become a real issue - you're not the first or last to mention the options page not showing up. It's become a bit of a pain really - I can't track down what the issue is, I'm actually using the recommended code for adding option pages verbatim. If you can tell me what additional plugins you have, or any other information that's valuable, I'd truly appreciate it.