Look, I was thinking of someone from Poland, from Wrocław area, but I do not know anybody I could recommend there.
I went through tuning with my mechanic who did not know Pagoda - just based on the same sources as you describe and lot's of help from experienced colleagues on this forum and we practically got there (just need to measure final CO level).
I live in Prague during the week (Smichov), can come and take a look - but I am not an expert and unless there is something obvious, what I went through and learned may not be enough to help you.
Also: you may decide to write here what is wrong - there are experts here who have seen a lot.