logging user access?

I do something similar to track database record access.  It may work for you.  I have a hidden table called AccessLog consisting of 5 fields:  User Name, User Email, Table, Record Id, and DateAccessed.  This table has a 'Trigger on new record' with the script:

'User Name' := userName();
'User Email' := userEmail();
DateAccessed := now()

I then have a global function:

function AccessLog(table : text,id : number) do
    let al := (create AccessLog);
    al.(Table := text(table));
    al.('Record Id' := id)
end;

And finally, on all my tables I have a main Tab element (on to which the fields sit) with a 'Trigger before view' script that calls the function:

AccessLog("TableX", number(this.Id))

Every time a record in the table called "TableX" (or whatever) is accessed a new entry is added to the AccessLog.

Doesn't log IP address, but you can see when they last accessed any records which probably indicates when they "logged off".