“All parts should go together without forcing. You must remember that the parts you are reassembling were disassembled by you. Therefore, if you can’t get them together again, there must be a reason. By all means, do not use a hammer.” —IBM Manual, 1925
What’s sad is how many people will only remember him as Flounder. Vir was so much more of a stretch for him as an actor. (Who killed the mad Centauri Emperor? It wasn’t Londo.)
I know he’d been battling health issues since Babylon 5 was still in production – at one point he minimized his appearances for a while and came back to the show much thinner. Despite that, I guess those problems still caught up with him.