The UI Interface is not working properly for SpellForce - Platinum. Cannot highlight text, such as when picking which saved game I want to load. The health and mana bars on selected units/heroes/avatar/buildings are not showing. The green/blue/red rings around selected units/heroes/avatar/buildings are not showing. I'll have one unit selected in a group of multiple units, but cannot tell which one it is. I cannot tell how wounded or damaged selected units/heroes/avatar/buildings are.
I am running 1.54 version of SpellForce - Platinum in 1024 x 768 x 16.

Switched to a new computer last X-mas:
Windows 11 Home 64-bit
Processor: AMD Ryzen 7 5700G with Radeon Graphics
DirectX 12
Card name: AMD Radeon RX 6600 XT
Chip type: AMD Radeon Graphics Processor (0x73FF)

Now I know there is a fix for this, because I had the same problem 4-5 years back on an older computer. Just forgot what it was, heh.

...

Went to that site, as you suggested. Downloaded the exe, but it would not work when I dbl clicked it. Four "SpellForce V1.61.exe - System Error" pop-ups about "The code execution cannot proceed because blahdeeblah was not found." First V3D9.dll, second ProjectClientAPIReleaseWin32, then it's binkw32.dll, and lastly mss32.dll

Soooo, didn't work.

Game subforum might be of use: https://www.gog.com/forum/spellforce_series#1712835212