Hard to say based off the photo. Try compiling the map to get a feel for the size of the space and be sure to pick a medium speed class as to not have a bias due to speed. Then you just go from there and adjust
Interesting Fact. I used Valve Base as the basis for my 2020 April Fools map, e1m1mountainlab
Never underestimate how little motivation you are going to need to go back to a 10-year-old thread and download a blocked-out version of Mountain Lab.
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