I just downloaded x581c01.dat into my Unofficial/parts folder, and then loaded it from there. LDView automatically downloaded the subparts into Unofficial/parts/s, and the file loaded fine. When you say "unofficial folder (in the s folder)", do you mean Unofficial/parts/s? Because if you put the files elsewhere, it probably won't work.
Also, if you enable LDView's automatic download of unofficial parts, it should download the subfiles automatically (and the motor itself also, if you load a file that references it).
Are you by any chance running on Linux? Because I notice you're using capital letters in the filenames, and that might cause problems on Linux on a case-sensitive file system. However, if you let LDView download the files for you, there shouldn't be a problem.
Also, if you enable LDView's automatic download of unofficial parts, it should download the subfiles automatically (and the motor itself also, if you load a file that references it).
Are you by any chance running on Linux? Because I notice you're using capital letters in the filenames, and that might cause problems on Linux on a case-sensitive file system. However, if you let LDView download the files for you, there shouldn't be a problem.