How to disable the terrain model or lower it's resolution?

[ArcherAC3]

Hello, all.

I have a very low-end system with no chance of upgrading it any time soon, and been trying to find a workaround for the bad performance I'm having with TacView.
The issue is that my Video Card is of an older Fermi model which does not support the Vulkan API required by TacView - this seems to force my CPU to handle the graphical part (if I may say so), raising CPU usage to 100%.

I noticed, though, that this only happens after the terrain is fully loaded.
By openning an ACMI file and setting it to play (which it does, albeit at ~5 FPS) I tried switching the terrain model, which causes another model to gradually load - while loading, the terrain quality is gradually increasing, giving me ~60 FPS with fluid animations at it's lowest quality and gradually worsening the performance as quality increases.

If there was a way for me to disable the terrain completely - setting it to like it is right after you launch TacView - or lower the terrain quality (sharpness), I could probably be able to run TacView at a "watchable" FPS until I get a newer videocard. Low quality terrain or no terrain at all aren't problems at the moment, as I need TacView primarly to be able to view the relation between different aicrafts (distances, heading, aspect, etc), and not "where" over the globe these aircrafts are.

One of the things I tried, to no avail, was switching the "Terrain Display Mode" to "Empty" - it doesn't work because the terrain model itself is still loaded, although it's like if the whole "world" was grass/flat ground.

Any tips/suggestions are welcome.
Thanks!

[ArcherAC3]

Here's an example of the low terrain quality I was looking for: https://imgur.com/a/iSbfT2k

If it'd stay this way (blurry), without the quality increasing, it would be perfect.