From the Report Templates grid in the Administration pane where you exported the report template file from your other database, instead select on the grid menu option Import Template -> browse to the location of your ayr file -> select it -> select Open -> then it will be imported into that database.
Screenshots and step by step of this is in the AyaNova 4 Help file section on Report Templates - Importing a Report Template (URL removed as for older version no longer supported - see the latest version of AyaNova)
Do note if you get the following message "Selected report can not be imported: There is already a report with the same internal ID value in your database" when importing the report template into the database it is because you already have that report template as identified by its internal ID in that database. It could be that the report template you are importing was originally a sample report template that we provided but you further customized it, instead of saving a copy and customizing that copy which would have given it a new internal ID. If this is the case, you need to figure out what the existing report template is in this database and delete it before being able to import this report template - i.e. what was the original name of the report template that you edited and changed the name of, delete that.