Browsing classical music by composer and genre

i’m using Roon for the first time, thanks to 14 days trial, after a life spent using Media Center / JRiver and I’m facing some problems browsing my music library.
My collection contains only classical music and it’s nicely tagged by composer, genre (chamber, instrumental, opera, orchestral…), period (20th century, romantic, classical, baroque…), work (which is the composition name, Quartet for Strings No. 12 for example) and all the other tags for artists, ensemble etc etc.
I’ve imported the library in Roon and made sure to use the data from the files but i still can’t display the music as I’d like, first by Composer and then by Genre (chamber, instrumental…). The ‘Focus on’ button allow to select instrumentation which I have no idea where it’s coming from, it’s not in my tags. And it’s also pretty useless (mixed trio? Solo instrumental for a Violin concerto?)
I also tried to remap the genres, but Roon seems to mix them with Period, so I basically get 20th century in the same category as Instrumental.
I’m sure I’m doing something wrong here, but I’d really like to understand what. I’d have no problem updating the data in the files according to what Roon is expecting, but I’m not sure how it is handling the metadata in the flac files.
As it is the trial is pretty useless as i can’t find the music I want.

Thanks in advance,

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Fair enough, it looks like there’s no way to do such a simple thing…back to JRiver. The lack of support for a product costing $700 is impressive.