You have to look at the used datfile and how it specifies the sets.

Then check your rompaths and see how the general loading rule

rompath\setname\file 1.... file n or
rompath\setname.zip/.rar/.7z

is used for that specific datfile.

You said "all [U], [J], and other releases into one archive to save space", so your datfile has to like:

game (
name my_test
description
rom ( name test[u].bin ... size ... crc ... )
rom ( name ..[u]... size ... crc ... )
rom ( name ..[u]... size ... crc ... )
...
)



But then you only got one set 'my_test'. For storing/scanning it means:

rompath\my_test\test[u].bin ....
or
rompath\my_test.7z (or .rar/.zip)

If you want to keep your files archived as well, your datfile has specify more sets

game (
name set_1
description
rom ( name test[u].bin ... size ... crc ... )
)

game (
name set_2
description
rom ( name ...[u] ... size ... crc ... )
)

game (
name set_2
description
rom ( name ...[u] ... size ... crc ... )
)



Roman Scherzer