I am certain that at one point GOG included the latest community patch (1.75.14) in their installer, but it is now at 1.74.14. Please change it back.

Thank you

I suspect there are two main reasons why 1.75 is not on GOG:

1. Patch 1.75 is not customizable (if I remember correctly - I may be wrong) in respect to Video Settings - it is way more demanding - and many people still don't have powerful enough computers to play it properly (for example 1.75 require a video card with a min shader of 3.0, while 1.74 supports even 1.4!). This probably made a lot of players unhappy.
From patch notes:
"+ Resource cache can't be changed manually anymore, but will be calculated automatically instead.
+ Autodetection of adequate graphic settings improved.
- Support of shader 1.4 and 2.0 removed.
+ Rim lighting, soft water and soft particles can't be switched off anymore."

Who wants to install a game and then downgrade it when upgrade is so much easier?

2. There may be issues of Legal nature. I don't know for sure if this is the case, but it may as well be a good reason for it.

Apart from all these, you have a far better chance of getting a straight answer is you contact Customer Support about it. Those guys a re really helpful, regardless of the problem.

Cheers.