If you are having trouble with getting you specials to go off, watch you action ( or mind ) and make sure you have enough.
For Spy:
Venomous Ploy: From what little PvP I've done, I've tried to use this as a way to block my opponets movement ( a total of one time =P ). For PvE, it's works great to draw an mob into.
Smoke Cloud: Stims do not break smoke cloud. Your heal ability will. What I found that works really well is that I run in and hit Venomous Ploy and draw agro. Someone else follows in close behind me. The mob works on my health until I used up my heal and then I use Smoke Cloud. This (usually) breaks me out of combat and I start to heal real fast. The mob then swaps over to someone with full health. My Heal will be ready before my stealth breaks and I usually get another stim in as well. I break out of stealth with my heal and I can start attacking the Mob. Batak and I have taken down super battle droids this way.
Arachne's Web & Spy's Fang work well together. I've seen them do noticeable damage to a mob while I was laying on my back waiting to clone on the corvette

Flash Bang: From what I've read, this is suppose to be a speed debuff. Not sure yet how to use this special ( or if it's working properly ).
For Jedi ( not really a special but a replacement until your's are fixed):
Look into Cryoban grenades. Grenades are level restricted now and not profession restricted to Commando anymore. Cryoban has a snare effect as well as a speed debuff from what I can remember this late at night and not having the text discription to read. I also don't have any to test with at the moment.