Well, I used diffuse merge tool to compare both the .sql files and found 2 little diferences. For one instance the line:
ALTER TABLE `customers` ADD `mmstatus` CHAR( 2 ) NOT NULL AFTER `customers_newsletter`
-could not be found with mergetool so I imported it by hand. That gave me a .sql error. I replaced every `for ' and it worked. The database was made and gave no errors while using phpMyadmin. Then I used the .sql file without the above named code and...it imported without any errors. I thought this would be succes!
Nevertheless it didn't bring me any luck. Again I had a blank screen at admin and public part of the website.
I'm done with it. It doesn't work for me although it is still the addon I was looking for.