Hi, Alek14, I test-translated en-ja for the same enwiki article, but limited sections into my sandbox: I imagined three points which could possibly cause to reject CX2 output in dewiki. No past experience on en-de CX2 output, though, only based on my personal hunch working with CX2 with 200+ output pages;
- no infobox;
- multiple images before the "top section";
- could be any footnote problem caused by citation template mismatch.
Thus, I translated only the top section, with References and External links only. The outcome was fine, that en-ja CX2 output for w:en:Quadruple_glazing was successful.
- In stead of applying four images at page top, I grouped them per two images;
- I did not finish translating all sections, but
:* Special features of ultra-low U-value glazed buildings;
:* Multipane glazing engineering;
- See also;
- References;
- External links.
Not sure if your problem links with my test case, and I would need to finish those two longer sections which I have skipped this time. Cheers,