From readme: V3.6 - Mass storage class overhaul. Now supports bigger physical block sizes for automounting of RDB partitions, FAT/NTFS and also CD/DVD drives, also adding a lot of emulation, workaround and new compatibility fixes. - Several fixes and changes regarding USB 2.0 support. - Reworked Prefs Handling, enhanced Trident. - Changes, fixes and enhancements in the main library. - New class supporting ethernet adapters using ASIX Chipsets. - New shell tool for the use of USB Rocket Launchers (no April's fool).
masstorage.class from previous 68k release works here fine. I have a mp3player with non-standard block, simply doesn't work with older massstorage.class. Poseidon mounts it as cd or dvd, but anyway it works ok .