ul_spring

Ok, this is me, trying to give some feedback.

http://postimg.org/image/y4qh1vtof/ You seemed to have used alot of stretched textures all over the map and it does not look good and realistic at all.
http://postimg.org/image/5t4x4u9rz/ The bhop blocks are good (they are set a bit too fast to go down, try 150 speed). But the textures are stretched and are not aligned properly
http://postimg.org/image/cywo7aiv3/ Stretched texture, looks bad.
http://postimg.org/image/jk9e71ypr/ Stretched textures and they're not aligned properly (to seem like there is only one continuous texture)
http://postimg.org/image/i91myl33z/ As stated in the picture, mixing different textures one after another looks bad. Try placing a wood pole in the corner or another kind of cool detail to hide the mixture, or just try not to mix the textures like that.
http://postimg.org/image/udgwfkfzz/ Long hallways. Making it go straight looks awful and not really realistic. Make it go in zig zag (like you did with a different section i will point out). Or use some more details along the hallways to make it less dull/empty.
http://postimg.org/image/nfhdnd79b/ It does not fit at all. Avoid using textures like that, expecially textures that have transparent blue in them.
http://postimg.org/image/h0drcyb5r/ Same shiet.
http://postimg.org/image/gu4nnlren/ Now this hallway is in zig zag, it already looks better than the other straight long hallways, doesn't it? But, always be carefull to the textures to be aligned perfectly and more important, fix the stretched textures.
http://postimg.org/image/tvqcdgfsv/ Blocks that are not aligned ( i suppose the textures were too). And add teleports to longjumps.
http://postimg.org/image/ss681hv5r/ Here i give you an example of a normal texture versus a stretched texture. Looks like poop, right?
http://postimg.org/image/4e7xtuy2n/ Don't use straight blocks ( i will have to repeat this alot). Use something like i've drawn in the picture.
http://postimg.org/image/8tqcz4agv/ Carve tool = NEVER USE IT. Make the path manually with vertex tool.
http://postimg.org/image/lmegz1m2n/ Ladder too fat yo! Make it smaller and alot thinner.
http://postimg.org/image/fbebfqr5r/ Ladder selfie.
http://postimg.org/image/r1s8x4jy7/ Square rooms = No no. Add stuff inside rooms and avoid using square blocks unless you're making blocktype map.
http://postimg.org/image/3xrs4jgn3/ Same shiet. But i'm noting there is not a single stretched texture in here, which is good.
http://postimg.org/image/qxyfgvegv/ Stretch stretch stretch =not good.
http://postimg.org/image/zb44bjdof/ Straight lines are not sexy. Make it more diverse or use the method i've shown in the picture.

Plus some light bugs and stuff which are not important for me

http://twhl.info/tutorial.php?id=32 you can find a way to make this arched hallway using vertex manipulation and not by carving.