No visit other than those of users of my Intranet network is counted even though there are visitors coming from outside the network?

If your Intranet network is behind a modem-router for example, it may happen that all visitors who access your server from outside are considered as having the same IP address. Therefore they are counted as ONE visitor.
This problem will be fixed in a next version of phpMyVisites. That version will feature an improved detection algorithm.