Now our database is empty and we can't test it, sorry.
The problems the scalability detected with 40.000 users are because the table acs_permissions have 500.000 of rows.
We have decided not to create all the users once and for all and we will only have about 15.000 students and we hope not to have problems with the perfomance.
When you are ready, I can make a tag shortly before your launch so you can launch on an official version.
It is not necessary that you make us a tag, thanks. But if that we would like to include the Catalan language in the branch of the cvs oacs-5-1. We have translated the platform to the Catalan language in the translate.openacs.org.