Whatever you put in "C:\Program Files\Ziegler-Tools", it is not where TransDEM 2.6.0.0 is installed. That must be somewhere else. The 2.6.0.1 patch will only work on the correct installation folder.
(I would also recommend not to store any user data in the Windows program directory. Trainz may have lead to bad habits as N3V did not observe the simple separation rules of program and user data before T:ANE, in place since ages, but kind of enforced in Windows only since Vista. This is always a bad idea. Leave Windows UAC - User Account Control at its default values and and you are much better protected.)