Shopping Cart 4.67 DNN6.0.2

I had shopping cart 3.96 installed on the site when it was a DNN 5.x site, but we never really used it.  I learned from you that I needed to go to the latest release to work on DNN 6.x so I purchased your latest release SC 4.67 this moring.  Becasue we never really used the previous version of the shopping Cart I Uninstalled/Deleted all of the  Shopping Cart modules.

The I tried to install SC 4.67, but I got a temporary loading error - see the attached screen shot in [loading error.docx]

I recycled the application pool and cleared cache and then tried to  install again. This time I got a bunch of SQL errors becuase the table were already there and it was trying to insert duplicate columens.  So I went to host --> SQL and dropped the tables it was complaining about. -  see the attached document with the list of tables I was dropping in [table drops.txt]  I tried to install multiple times but it kept finding more and more duplicate tables, so I would add to the list to drop and then install again.  But when it got to object Smith_AddVMatrixDetail  was not able to drop it.

You can see in the attached [installtionerror.doc] the last error and the list of modules that are installed (or at least it says they are installed in host --> extensions) and at version 4.67, but the Smith Buy Now module is not installed. 

I do not undersand why I am having this problem, the install says it is repairing, but I am getting errors on duplicates and the BuyNow moduel has not been installed at all.  I need assistance to get a clean and correct install.

Please advise!

Judy