Got it, my 2nd read was that 'Always Free' and 'Extended' were 2 product versions. The only super clear call to action I saw was 'subscribe', the only mention of it being free is buried in a paragraph that's well below the fold. The only mention of it being open source is in the footer.
The download buttons somewhat imply it being free, but it's relatively common for crippled/time-limited versions to be offered like that.
Basically - I think you could benefit from making it more obvious that it's free (and open source), with optional extra paid stuff. Probably a clearer link to the online version as well.
