Default Simbrief plan abbreviation is DEP airport + DES airport usually followed by 01 before the file prefix. (.fms/.fmc e.g). Speaking on behalf the 700 and 900, I haven't tested in flight, but should work the same way as zibo´s. As for most issues regarding NG, Zibo, Ultimate, can be solved with google and critical thinking. If there are no flight plan routes in the FMS Output folder in X-Plane, Simbrief isn't loading in via downloader. They need to be set manually both shortcut and confirm outputting into f.e. AviTab and said Output folder. There are no shortcuts in life - and as should be applied accordingly. Except shortening the STAR, personally hate planning for long ... STARs, lol.
Speaking of AIRAC cycles; the latest will be the last to compatible with 11.41. (Source: If you are a navigraph subscriber, check your mail about cycle changes.)