What you need to know:
How to swap meta
How to do it:
1.Open any map that doesnt have a vehicle in it already, even prisoner.
2.Go to the [vehi] tag, take what vehicle you want (i mostly use the ghost cause its small)
3.Goto the [scen] tag list, paste the meta over anything you want to be a vehicle ( i recomend the flag base, cause then its only 2 vehicles, and its at both bases)
Thats all there is to it

I dont recomend adding ALOT of vehicles to small maps like prsoner or wizard, and dont add them to chirion, theres no point...
EDIT
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Ok, also you can use this to add more weapons to the map, like the gravity rifle or whatever, or maybe the needler and not the MP needler, you know... so you can have a needler thats normal, and a needler that shoots a trillion needles lol.