when I recorded video was named as "env_sidewalk02", but now is name "env_sidewalk" and happens me the same. The weird is happens only when I put that texture. and I didn't give it any special propety (func_ "something" or trigger)
What is that texture assigned to? Personally I'd avoid starting any names with "env_" as who knows what weird hackery was done to make the engine work. Seems more of a case that the brush you've assigned that texture to is an illusionary or doing something weirder.
The only thing i can think of is that the name was too long. 15 bytes is the maximum, and the game only considers the first 12 when doing material lookup. Could be the name happened to trigger a bug in that code.