Your version 1 templates are compatible with version 2, however in order to utilize all the new features you will need to update your templates.
Updating the module: After you upload the module you must click the module button, or else.
1. Templates: If you have customized your templates it is possible that something might not work as expected. If you are using stock templates, then there is no problem.
2. Htaccess file: For feeds, AMP, archives, and other features to work, you must update your htaccess file in the Scot's Blogger configuration. If you have customized your htaccess settings do not automatically update. Most of you won't have an issue with this.
Installation (and links to new templates):
Miva Merchant Module Update Detailed Instructions
If you've never updated a module in Miva Merchant before it's easy to wonder if you're doing it right. This should help answer your questions and will work for any module that you need to update.
1. Open the MODULES section from the main store menu.
2. Search for the "scotsblogger" module.
and then move your mouse to the left of the module code (under the gray checkbox) and click on an "open" button that will appear.
3. Click on the "files" tab, then the upload button. It will open up a little upload box. Make sure you check the "overwrite" box. Then find your new file and upload.
4. After you've uploaded the new module, click on the green update button. Do not forget to do this.