Google Pro Maps error and multiple locations

I get the attached 'Error in MakePages' when I launch Pro Maps. I click 'OK' and it opens the panel. I enter my API key and go to 'Next' screen and 'Multiple Locations' checkbox is greyed out. Just using MySQL not MySQli and I wand to create a dynamic map with multiple locations.
What can you suggest?
Thank you.

That looks like the error you would get in DW 2015 before we made the latest update. Try uninstalling and reinstalling the Design Extender extension and the error should go away in the latest update.

Using CC 2014 but OK I'll try that. Question: I lose my DE presets if I reinstall?

No, presets should be maintained. If you want to be extra careful you can backup you Dreamweaver user's configuration folder before uninstalling to keep a backup of all the settings and files that might be manipulated during the installation process.

OK I finally circled back on this as I expected issues might arise on the reinstall. As noted above, I'm using DW CC 2014.1 not 2015. Downloaded, installed DE 1.21 and reopened DW.
1> I got the attached error repeatedly by just opening DW
2> I clicked it away just to see if my presets were still there. Activated DE and when I opened both Google Pro, the multiple locations box was still greyed out and then I opened CSS Menuwriter, it showed my presets but when I clicked on them i got "The database connections for this content preset do not exist in this site. Please create the following connections to use the preset GSCsql." GSCsq.php does exist already in my/Connections folder from when DE 1.2 was installed and working before.
3> Just for info, I tried opening DA and it could not find the SQL connection and then started kicking out the same error attached. On retry, it won't even open.
I did backup the DW/Configuration folder as you suggested before the install if that helps.
Help please - I'm stuck as even without accessing WA products DW is popping the attached error and preventing me from working.

That looks like an issue that could be solved by clearing your cache .dat file.

Please follow the instructions outlined here and I believe it will solve your issue: http://www.webassist.com/community/tutorials/view_tutorial.php?tid=95

Thanks. Clearing the cache did stop the errors and other odd behavior. Still get a greyed out checkbox for multiple locations. Even if I enter a static location and insert it, I get the attached error below despite having obtained and entered a Google AP key. Now this is on wamp server and maybe it has to be live to work - not sure, but would still like to be able to use the multi-location dynamic address feature if possible.

This error means the API key you entered is not correct. The current version of pro maps doesn't require an API key at all, so leave that field blank in the maps UI and this error should go away.

Tried with no API key - result:
1> Multi location box is still greyed out
2> entered single location to see if that even worked. could see the Map placeholder in DW design view but nothing appears in the Live view.
Maybe you can take a look together when we talk later unless you have some other suggestion in the meantime.

Can you send me a screen shot of the muliti-location checkbox you are referring to?