Some Entity Confusion

I am unclear about how to use some entities and how they work. Any info about any of these entities will be very appreciated. Thanks.
Most of these entities are used with HL: Opposing Force or regular HL:

Also let it be known that I did check the VERC entity list but I still need more info about usage and their functions. In most cases the VERC entity list does not explain the entities.

1)env_blowercannon (no matter what I do with it I can never get it to work...it usually ends up in crashes)
2) info_pitworm_steam_lock
3)info_op4loader (is it possible to make it attack players) 2.(how do you make it drop the box it is holding like in the campaign)
4)path_corner vs path_track

Thanks so much for the help.

I guess nobody has any ideas about any of these?

I gtg to school now but just a quick message that may help until I'm back, try the site http://twhl.info

It has a great collection of entitys

---

Youtube Channel: https://www.youtube.com/c/Nibgames

There is a map, OP4 Park I think it is, has a shitload of tracks. Decompile it.
It might even have your other ent issues.

---

The best things in life, aren't things.

Thanks for the ideas. And I'm checking that link out now.