You could create a custom event module that awards 25 points on every u_register event awards 25 points to the given user. To do so you need to update the field "bonus" in the table qa_userpoints, if I'm not mistaken.
Or you could override the function qa_create_new_user() (also in a custom module) and do the database update there.
Is the operation "Add for all users" in admin/points can meet your requirement?
Welcome to the Q&A site for Question2Answer.
If you have a question about Q2A, please ask here, in English.
To report a bug, please create a new issue on Github or ask a question here with the bug tag.
If you just want to try Q2A, please use the demo site.