Check character/target buff/debuff time left by spell id:
Use condition type "C Sharp Code" with Value:
wManager.Wow.ObjectManager.ObjectManager.Me.BuffTimeLeft(new List<uint> { 69369 }) >= 1000
Replace "69369" by your buff/debuff ID.
Replace "Me" by "Target" to check buff/debuff on current target (you can also replace "Me" by "Pet" to check on the pet).
">= 1000" check if time left is "Bigger or Equal at 1000 millisecond", you can replace "1000" by required time left in millisacond. You can also replace ">=" by "<=" to check if "Smaller or Equal", or by "==" to check if "Equal" - http://www.tutorialspoint.com/csharp/csharp_relational_operators.htm ).
To get list of player/target (de)buff id, you can go to tab "Tools" > "Development Tools" > (if you want check your target (de)buff select npc in game) > click on "Player/target buff/debuff".