Looking nice, Youme. Though, and i fear being pedantic over aesthetics considering the content of the last 2 pages may simply get me a slap, your wooden supports are quite "blocky". Dustbowl's spawn feature's func_detail supports made to the same circular shapes and with the same texture as the wooden trusses you (and Valve, in Dustbowl and other mining themed maps) have used in the doorways. It would look so much nicer and match the TF2 theme that little bit more if you utilised this recognisable mining feature. Plus i know you have the capability to make basic models in Blender. Which might be appropriate given the amount of supports you have running through your tunnels. If you are going for the gravel pit style though (which does still utilise a couple of these trusses). I would recommend making some of the supports less uniform, IE make them look like they're collapsing or degrading, throw in some wooden planks along the horizontal, between the vertical beams.