installed texture pack, unable to shift click or right click in the inventory, chest, crafting table, etc.

I had downloaded a new texture pack for Minecraft, called David's Detailed 64x64. when i started to use it, everything worked fine. but i noticed that when i was in my inventory, i could not shift click or click the item i wanted to grab. instead, i had to old the left click and bring the item to where i want it. this also happens when i tried using the furnace, chest, and anvil. i dont know how to fix it. PLEASE HELP!!