I understand you are upset, I would be upset to if I found a link to software I have been looking for, only to discover it was not free after all.
In the case of Network Probe, it was free for all to use until version 0.5, but at that point it's performance and memory usage was still not optimized the the where we were satisfied with it. That is the reason we are not offering version 0.5 anymore. Unfortunatly some of the old links advertising the free version has not been removed or updated.
Version 1.2 still gives you quite a lot of useful information for free.
I am terribly sorry about your being upset, it is far from intentional, but rather a natural consequence of the evolution of software.
Regards, Bjorn J. Kvande President ObjectPlanet, Inc.