The uMediaLibrary folders are present regardless of trial vs registered version. Perhaps you're not finding it because the .dBpoweramp folder is considered hidden by Linux as it's prefixed with a dot (.) ?
Please try the following:
Code:
cd ~/.dBpoweramp
ls
And see what it prints.
Folder listing from my machine (has leftovers from different Asset versions though)-
Code:
p@debian-lite-32:~$ find .dBpoweramp/
.dBpoweramp/
.dBpoweramp/dBpoweramp
.dBpoweramp/uMediaLibrary-v3
.dBpoweramp/uMediaLibrary-v3/AssetStatus.bin
.dBpoweramp/uMediaLibrary-v3/LibraryUpdateID
.dBpoweramp/uMediaLibrary-v3/FilenameHash.bin
.dBpoweramp/uMediaLibrary-v3/MediaDatabaseFieldsv5.txt
.dBpoweramp/uMediaLibrary-v3/AssetUPnPForceToLPCM.txt
.dBpoweramp/uMediaLibrary-v3/AssetUPnPForceToMP3.txt
.dBpoweramp/uMediaLibrary-v3/MediaFoldersWatch.txt
.dBpoweramp/uMediaLibrary-v3/XRegistry
.dBpoweramp/uMediaLibrary-v3/AssetConfig.bin
.dBpoweramp/uMediaLibrary-v3/AssetUPnPForceToWave.txt
.dBpoweramp/uMediaLibrary-v3/XRegistry.lock
.dBpoweramp/uMediaLibrary-v3/uMediaLibraryMainDBv5.bin
.dBpoweramp/uMediaLibrary-v3/AssetUPnPForceDoP.txt
.dBpoweramp/uMediaLibrary-v3/asset-debug-lib.txt
.dBpoweramp/uMediaLibrary-v3/Asset-SystemUpdateID
.dBpoweramp/uMediaLibrary-v3/AssetUPnPForceSingle.txt
.dBpoweramp/uMediaLibrary-v3/SupportedExtensions.txt
.dBpoweramp/uMediaLibrary-v3/ArtStorev5.bin
.dBpoweramp/uMediaLibrary-v3/UpStreamArtFor.txt
.dBpoweramp/uMediaLibrary-v3/AssetUPnPDefinedBrowseTreev5.txt
.dBpoweramp/uMediaLibrary-v3/asset-debug-asset.txt
.dBpoweramp/uMediaLibrary-v3/AssetUPnPDefinedAudioTypesv5.txt
.dBpoweramp/uMediaLibrary-v3/MediaExcludeExts.txt
.dBpoweramp/uMediaLibrary-v3/lock
.dBpoweramp/AssetReg.bin
.dBpoweramp/uMediaLibrary-v2
.dBpoweramp/uMediaLibrary-v2/AssetStatus.bin
.dBpoweramp/uMediaLibrary-v2/AlbumArtStorev4.bin
.dBpoweramp/uMediaLibrary-v2/AssetUPnPForceToLPCM.txt
.dBpoweramp/uMediaLibrary-v2/AssetUPnPForceToMP3.txt
.dBpoweramp/uMediaLibrary-v2/MediaFoldersWatch.txt
.dBpoweramp/uMediaLibrary-v2/lock-db
.dBpoweramp/uMediaLibrary-v2/AssetUPnPForceToWave.txt
.dBpoweramp/uMediaLibrary-v2/AssetUPnPForceSingle.txt
.dBpoweramp/uMediaLibrary-v2/SupportedExtensions.txt
.dBpoweramp/uMediaLibrary-v2/AudioFilesIndB.bin
.dBpoweramp/uMediaLibrary-v2/AlbumArtIDXv4.bin
.dBpoweramp/uMediaLibrary-v2/UpStreamArtFor.txt
.dBpoweramp/uMediaLibrary-v2/AlbumArtUpStreamv4.bin
.dBpoweramp/uMediaLibrary-v2/uMediaLibraryMainDBv4.bin
.dBpoweramp/uMediaLibrary-v2/MediaDatabaseFieldsv4.txt
.dBpoweramp/uMediaLibrary-v2/AssetUPnPDefinedBrowseTreev4.txt
.dBpoweramp/uMediaLibrary-v2/MediaExcludeExts.txt
.dBpoweramp/uMediaLibrary-v2/lock
.dBpoweramp/uMediaLibrary-v2/AssetUPnPDefinedAudioTypesv4a.txt
.dBpoweramp/Asset-ID
.dBpoweramp/uMediaLibrary-v4
.dBpoweramp/uMediaLibrary-v4/AssetStatus.bin
.dBpoweramp/uMediaLibrary-v4/AssetUPnPCollections.bin
.dBpoweramp/uMediaLibrary-v4/AssetUPnPDefinedBrowseTreev6.txt
.dBpoweramp/uMediaLibrary-v4/LibraryUpdateID
.dBpoweramp/uMediaLibrary-v4/FilenameHash.bin
.dBpoweramp/uMediaLibrary-v4/MediaDatabaseFieldsv5.txt
.dBpoweramp/uMediaLibrary-v4/AssetUPnPForceToLPCM.txt
.dBpoweramp/uMediaLibrary-v4/AssetUPnPForceToMP3.txt
.dBpoweramp/uMediaLibrary-v4/MediaFoldersWatch.txt
.dBpoweramp/uMediaLibrary-v4/XRegistry
.dBpoweramp/uMediaLibrary-v4/AssetUPnPForceToWave.txt
.dBpoweramp/uMediaLibrary-v4/XRegistry.lock
.dBpoweramp/uMediaLibrary-v4/uMediaLibraryMainDBv5.bin
.dBpoweramp/uMediaLibrary-v4/AssetUPnPForceDoP.txt
.dBpoweramp/uMediaLibrary-v4/asset-debug-lib.txt
.dBpoweramp/uMediaLibrary-v4/AssetUserUpstreamImages
.dBpoweramp/uMediaLibrary-v4/AssetUPnPForceSingle.txt
.dBpoweramp/uMediaLibrary-v4/ArtStorev5.bin
.dBpoweramp/uMediaLibrary-v4/AssetUPnPExclusions.txt
.dBpoweramp/uMediaLibrary-v4/UpStreamArtFor.txt
.dBpoweramp/uMediaLibrary-v4/asset-debug-asset.txt
.dBpoweramp/uMediaLibrary-v4/AssetUPnPDefinedAudioTypesv5.txt
.dBpoweramp/uMediaLibrary-v4/MediaExcludeExts.txt
.dBpoweramp/uMediaLibrary-v4/lock
.dBpoweramp/uMediaLibrary-v4/AssetUPnPUserRenameList.txt