Did a little research today and wondered if the released agents could be related to tricothecene mycotoxins. Don't know how to do links, etc, since I just registered, but my search started with a link from free republic to global security.org using the symptoms of vomiting, rash, wmd. Various forms of this mycotoxin can be created, I guess, but what stood out were the symptoms of nausea, vomiting, diarrhea, skin irritations and unlike most microbial toxins, it can be absorbed through the skin (the sticky residue you mentioned). From other searches, it seems the Russians did testing in Laos in the 70's and in Afghanistan in 79 and possibly later. Also found references that similar stuff may have been used by Iraq in the Iraq/Iran war. Other known WMD's like anthrax, ricin, mustard gas, etc. didn't appear to have all the symptoms you mentioned and in the appropriate time frame. There also seems to be a variety of these mycotoxins which may have more (or less) severe symptoms. Best way I could understand this type of agent was a really nasty mold on steroids. Goodness knows how it would act if mixed with other "things".
Anywho, for others who are way more knowledgeable in this field than myself, please comment on/correct my theory.