Yes. I try to import the RAP from DEV environment in our TST environment. The Creation Date and Instance count mentioned on the right on the second screen of the Import wizard tell me the old .zip is still used instead of the new one.
I started with creating a new instance of Product. On pressing the Create product file, I get a new version of the .zip, and another number of records exported. This is the number of rules I expect to see when importing it on the other side.
It seems the same problem. When I do the export and use a new name, I end up with a smaller (correct 83 rules) file, where as if I reuse the same name, the file created is markably bigger (117 rules, as some rules were excluded after the first export). Trying to import this file (even with the name of the .zip modified to the old name so it should be overwritten in the TST environment), it actually mentions the right number of rules.