'system.outofmemoryexception' importing SQL script

Hello,
I need to import a database from SQL Server Express 2012 to SQL Server Express 2008.

I've used this how to

https://www.mssqltips.com/sqlservertip/2810/how-to-migrate-a-sql-server-database-to-a-lower-version/

The script generated is about 1,7GB and when I try to import it I receive the error "exception of type 'system.outofmemoryexception' was thrown".

I'm on a PC with 8GB of RAM, i3 4130 and SSD 250GB.

Any suggestions on how to resolve this issue'

Thank you.