It's sad, but true
About an app that's made me blue
It got my beachball spinnin' 'round
And brought me a cookie when it came down....
(With apologies to Dion)

I first downloaded freePhotoConverter 2.4 and it works pretty much as hyped and indeed seems to be "rock solid" except for its annoying habit of opening a Finder window without being asked to when it finishes its work.
I downloaded 2.5 several times and could never get it to launch.
Ditto for PhotoConverter 3.0b13.
At this point the developer sent me a link that appeared to be to b11, but all it did (on the very same day) was take me to a web-site selling Dell computers (Dells???) that has been identified to me as a "shady" one that collects information. When I questioned the devloper about the missing b11 I was told something like: Oh, we pulled that build.
Several downloads of 3.0b20 also hung and never launched. The developer has advised me that this is a compiler problem that affects some configurations (without having the foggiest idea of what my configuration might be).
But here's the kicker: When you download PhotoConverter, the very first thing it downloads is a COOKIE (An app plants a cookie? Yes, he said!) from home.hetnet.nl.
Now what the hell is that all about?