Hammer not starting after DLC update
I've just been informed by a valve employee that they're working on it.
Guess you should be working with the easy map maker then
EDIT: I'm sorry, moderators...

Maybe you used Noclip a bit, they have the arrival and depature elevators in the map, but you can't reach them (or did I something wrong?).
The next point: the "random" tiling at the walls isn't in the final map. All just the same textures.
The only thing this editor brings to us Hammerers are the new models, especially for the paint dropper modern style!
Skotty wrote:
Maybe they just wanted to give us time to explore the new map editor. I did it and its... far too simple for me. I only would like to have an auto-connect of the blue lights between testing elements in Hammer sometimes
Maybe you used Noclip a bit, they have the arrival and depature elevators in the map, but you can't reach them (or did I something wrong?).
The next point: the "random" tiling at the walls isn't in the final map. All just the same textures.The only thing this editor brings to us Hammerers are the new models, especially for the paint dropper modern style!
The elevators used to be far away connected with worldportals, this to prevent problems with overlapping elevators/tests
Random tiling in the map is something that might be implemented later.
Also: cube dropper instances drop straight down and fit in a 128x128 space.
The flip panel is awesome to use.
The new funnel model is small enough to fit in 128x128 
Download and extract this to something like common/portal 2/bin_old - DO NOT OVERRIDE, IT WILL BREAK PORTAL 2. Copy your current bin folder to something like bin_new.
When you want to use hammer, rename bin_old to bin. When you want to test maps or play portal 2, switch it back and rename bin_new to bin.
It's a bit annoying but at least you can use hammer.
Side note: the old one doesn't include the updated vbsp.exe or portal2.fgd, so you might want to copy those over from your new bin folder.
I feel so dumb now for not making a backup of my Steam folder before downloading that update.
I always think about that except when things actually break 
Anyway, let's hope they fix it soon.
Quote from a valve employee if you're still experiencing problems with hammer:
Quote:
You'll need to delete vbsp.exe, vrad_dll.dll, vrad.exe, vvis_dll.dll, and vvis.exe from your bin directory, then re-verify your Portal 2 cache.The issue is that the build tools in SDK were colliding with the tools now packaged into Portal 2. By deleting the files, Portal 2 should put the correct files back on your disk.
Kaleido wrote:
I'm glad they fixed it this fast... I was about to be really pissed off.
It isn't fixed yet, at least I don't think so, that's just a loophole Josh found.
Portal 2 updated again, so this might be the fix.
i can usually fix this problem by restarting (no other way works), but now i've restarted at least 5 times and nothing has worked.
Wanderer2021 wrote:
It seems that everything is working for the most part now. I haven't gone in depth, but it looks like Hammer is working again, and now the in game editor is able to rebuild the maps for testing, though it took a removal of the authoring tools, verifying the game cache, then reinstalling the tools.
AND THUS WE HAVE A FIX TO THIS MADNESS