the stairs near B in the tall building dont have any collisions, thats probably on purpose but i feel like you could block them off in different ways

Do you mean the stairs blu base at stage 2?

there's a small spot near the blu spawn on stage 2 that you can stand on: https://streamable.com/lj180
there's a little wallbug you can do above the water deathpit on stage 2 where you can wallbug and then just stand on: https://streamable.com/s57a2
you can shoot fire through the stairs outside blu spawn on stage 2 at specific angles:
https://streamable.com/p1eth
the taller classes can also do visual glitches through the platform and look straight through it:
https://streamable.com/ypgln
on red spawn of stage 3 you can do the thundermountain guillotine glitch (both ways):
https://streamable.com/baf0w
https://streamable.com/cp4bo
and on a lot of the staircases that are made of single planks you can shoot through the top one, this one being the worst offender: https://streamable.com/7fted

Thanks, i'll look into these!

i showed more in detail how the top of the stairs outside stage 1 red spawn can be shot through (with dispensers): https://streamable.com/lwm1m
and i found one spot that seems unintended on the B point of stage 1: https://streamable.com/3bps1
on stage 2 specifically some of the A/B wooden signs don't have collisions, even though they do in a majority of the other spots, it's a very small thing but i feel like it would be better if they were all consistent with eachother.
other than these small unimportant nitpicky bug reports i really like the turnout of the map, it blends the styles of many other tf2 maps. nice open areas in stark contrast with the tight corners at the final stages. i really really like the final stage and its verticality :).

I have looked into these issues and fixed most of them already in my version. The fixes go out when i release it, maybe in few days. Thanks for digging into these, much appreaciated!

Hello! Me again!

I am posting here not to clog up the comments and I think this is the best spot to post this.

I had a look at the workshop folder, and unfortunately the navmesh isn't there. It's under the steamapps/workshop/content/440/2007331583 folder, and the only file there is cp_ambush_rc5.bsp

Thanks!

You misunderstood my comment before. The .nav file is packed within the bsp like everything else, custom materials and suchj, and works fine ingame. The reason for this is that you can only upload single file (bsp) into the tf2 workshop here on Steam. You can look inside the bsp with programs like GCFScape.