For the steam version try this as suggested by Gandalf.
-Rename bladesoftime.exe to bladesoftimeOriginal.exe
-Rename Texmod.exe to bladesoftime.exe
-Launch the game via Steam, it should execute Texmod instead of the game.
-Click on the folder icon below "Target Application" then select your bladesoftimeOriginal.exe.
-Now, you need to select the tpf, click on the folder icon just above the red cross and select a tpf file.
-Click run to load the game. Some antivirus may detect a trojan, that's a false positive well known of Texmod.
And because you are running windows 7 64 (same as my system so I know this works for the normal version of the game) right click on texmod (now named bladesoftime.exe) and go to properties and make sure 'run this program in compatibility mode' is checked with windows XP SP3 in the dropdown box below it.
Did all the instructions and this way I have not worked:(:(:(
