I just came across a problem with the most recent versions of HDL_Dumb (0.8.2 and 0.8.0): They don't seem to support 48-bit LBA for > 120 GB HDDs!
I just filled my PS2's HDD to the point which makes 48-bit support mandatory and HDL_Dumb 0.8.0 was telling me that there was no space left on my 160 GB HD, which was only filled with approximately 120 GB. I gave the latest 0.8.2 a try and it reported the same error.
Luckily, I stumbled upon an old version (0.7.3) and guess what: It works perfectly, correctly detecting my HD as being 160 GB in size and transferring the game ISO without problems.
So, what's the deal with the newer HD_Dumb versions and 48-bit LBA? Do they have to be patched manually or am I missing something here?
EDIT: I just tried to start 0.8.0 after transferring the game and it quits with "partition data across 128GB mark found". -__-