First you have to go into the GoblinEditor options screen and type in your SH5 install directory, in
2 places.
That's why I could not get my Goblin to work for a few weeks, I had only typed in my directory in 1 place.


See screenshot (relevant for my install!)
This will solve the missing actor dll problem.
Next step - very important.
Back up the ZON file for the sub you will be editing!
Then use Goblin to open the GR2 file for the relevant sub.
Then Merge the ZON file in.
Double click on the 'Colisionable Object' entry in the project tree to edit the behavior.
See screenshot
This is a shot of the ZON file for my Type VIIA.
You see it has a value of 250.
This does not mean 250 meters! The game seems to use some arbitrary scale for this value.
I found a useful bit of info about how the game calculates the crush depth from this figure last month, I think from the RUB forum. It looked good to have so I copied and saved it.
-- Note 1:
* Remember that crash depth is not a direct depth translation. Crash depth is obtained by taking your targeted depth, multiplying it by 0.3 or 0.4 ( I used 0.4), and adding that to your original number.
Example: My targeted crush depth is 230 meters, therego
( 230 * 0.4) + 230 = 322
I think this was originally written by either Ducimus or Luke, so thanks to them for figuring this out
After you have edited this and closed the window, the ZON entry in the project Tree will turn red, I guess to let you know you have changed something.
Right click on it and save it.
Job done, go test.

Be aware SH5 subs still have a bouyancy problem, exacerbated by going below 200 meters. Don't be surprised if once you get down that deep you need a lot of speed to maintain depth.
Good luck