Hello Ciaran,
today we did an J4 update to a customer website and installed J51 Emani as new template.
As always I configured the template option "custom.css" to YES.
In the database the value looks ike this: "customcss_sw":"1"
But in frontend there is no custom.css available.
The file "custom.css" is available on the server under "/templates/j51_emani/css" directory.
Caching is disabled.
If I add the css code to the custom csss field in the template options, then it works as expected...
Maybe I have done something wrong, but I have no idea. I have done this on more than 50 sites with your templates and it worked always but not in this case.... no clue...
Regards
Oliver