If you add a new file to your mod yes you need to add the entity.manifest file. If you are just editting gameinfo files I though all you needed was to put the modified files into the gameinfo file in the mod, but I could be wrong. Either way, Harpo has a nice manifest maker in his utilties that will generate an entity.manifest for you, which you can use if it still doesn't work.

ok so the files did come from the forgetools where would i get some new ones not in bin format and where would i get the program that harpo has?