Don't have the Sharn expansion yet, but I bought the new questline so I have now completed the Soulsplitter chain but the final quest had issues.

The splash screen states 2 new dungeons and 3 new explorer dungeons - but the chain is 6 quests (unless one of them is reused from existing Sharn questlines which seems unlikely...)

My first run of the final Soul Splitter on HE solo took over 2 hours and it failed - I completed everything I could, got the end chest, but I didn't tick the 'Find the HQ' requirement (even though I had obviously found it and trashed the place!), so fail...
When the lift appeared, it looks like the floor is trapped, so I pulled the lever from outside the door, (hopefully triggering the floor falling away into a pit of spikes, flame and acid without me there) assuming that I would always be able to call the lift back.
You can't.
If you are not in the lift when it sets off that requirement is never triggered and the lift door is replaced in the ship by the usual swirly sigil to transport you to the next phase (which is exactly where the lift would deposit you).
I DDoored back to the beginning twice, once because Dorris was following me on the minimap (blue dot was always behind me) but she was nowhere to be seen, which was awkward when I had to speak to her.
DDooring still didn't trigger the 'Find the HQ'.
The second DDoor was after the end fight to find the alternate body that was required, ran around the entire place, smashed everything, talked to everyone multiple times, went to DDOwiki, came to these forums, no clues. Eventually I used the advice channel and a kind soul pointed out what I'd missed. For anyone who doesn't already know, everything you need for the end scenario is in the end room (assuming you drag Dorris with you, and that she is required).

Ran it again today and completed, so that's fine for me as I've had my "Gotcha" moment, but I suggest making the Find the HQ an optional or to have it trigger if you use the swirly sigil thing that replaces the lift door, and make the soul splitter selectable with text before you trigger the mass release, just as a clue.

Overall I enjoyed the chain, even if some of the maps looked like they'd taken their inspiration from the dev that drew the map for 'The Pit' House D quest. Looking forward to Sharn proper being available in the DDOStore.