eCATT recording from login screen?

Hello everyone, I recently discovered eCATT and find it outstanding to automatize some administration tasks.

What I need it a script that lets me login to SAP with a different user/pwd each time read from a file.

My problme is the following: we have to create hundreds of users for the performance tests. Therefore I created them using SU10.

The problem is they all got random passwords, so I created a test script with eCATT that uses TCD and transaction SU01 to change all passwords for all users using an input field that reads a text file in my computer.

Here is the tricky part: the users must have fixed passwords. Given I just created them, even after unifying their passwords, the SAPGUI still asks for a new password on the first login. Obviously I cant log in for each user (too many)... is there any way to use eCATT with the SAPGUI(record) or similar starting from the initial login screen? I tried starting from transaction SAPMSYST but it doesnt work. Is there any way to tell eCATT to start recording from the login screen?

Any solution to this dilemma would be greatly appreciated

Thanks a lot

Sebastian