Help needed with eCommerce Coupon Install/uninstall

I've recently un-installed all ecommerce modules and deleted the directory. I was using one of the v4 dev modules. When I checked my database the only ec tables remaining were coupon and transaction_coupon so I deleted them manually so that I would have a fresh install of the latest stable version of ecommerce. I DL'd and enabled the ecommerce modules without a problem. When I installed Coupon I got a message that the settings had been saved, but nothing about tables being created so I checked the database and sure enough no tables were created. Does anyone know why the install file would not have been run? I also had this problem with the dev version, hence moving back to the latest stable release. Is there a record in the Variable table that I might have to delete? I've tried clearing the cache tables and that did not help. Any guidance would be greatly appreciated.