When we try to open the Chat DB, it takes for ever to build the view.

If you need the database to quickly open, you need to make sure that the views are always indexed and up-to-date.
The server discards any view-indexes if they haven't been opened for a while, or it needs to increment updates to them if they haven't been used for a while.

You could create a server PROGRAM document and schedule this task to run:

UPDALL imtchatlog4.nsf -v

(the -v option updates the view indexes). For details on what options are available, type
> load updall /?
on your server console.

If you schedule a program doc to run this task periodically, the views will always be up-to-date and the db opens immediately.