Hi all.
we was checking our pagerank (our site www.ff3300.com) with this free tool: http://checkpagerank.net/ (or other, it’s the same…)
we discover the result is 0.
But we have a lot of incoming links… and the SEO is correctly configured.
So, we tried to check other website done with kirby… and the result was the same.
So… the question is: why? 
What can we do?
The PageRank is not relevant anymore, you can read more about this on Wikipedia.
Aside from that, this question is not specific to Kirby as Kirby does not include any SEO features on its own.
Like @lukasbestle said. Don’t trust pagerank. Trust traffic, conversions and positions.
About the Kirby side of it…
It does not matter if you use Kirby or some other CMS. What matters is the HTML, speed, links and header status.
If you moved from another CMS, check that the links match the page exactly. For example WordPress uses ending slash, Kirby does not. Details like that could matter when it comes to inlinks.
If they don’t match you may need some redirects.