I also would like to add that, if the developers ask for more details on an issue, it is required to response with said details. This is the only way to work on the issues in order to fix them. If those details are not given the issue is considered as invalid or even as trolling and will be closed and ignored accordingly.

This issue has been closed as invalid.

Maybe a monitored testing session via remote view/access could bring some light in the dark. This way we could rule out any addon conflict or a corrupted game. Usually we do not do such extra support efforts, but this issue seems to be quite unusual and might be worth the extra effort.

Looks like crazy physics to me. Ususally the engine remove entities if it would crash the physics engine instead.

About the derail issue. This is what SligWolf was talking about:
https://steamhost.cn/steamcommunity_com/groups/SligWolfAddons/discussions/1/4513255384647889127/

It has been reported to the game developer and it is currently under investigation.
https://github.com/Facepunch/garrysmod-issues/issues/5968

@FruitBerryCrunch: Please check if the prop disappearing issue also exist on the non-beta branch for you. Make sure you test it in single player or in your local multiplayer. If using an online server make sure it has the same version/branch as you do.

This might be be cause of recent GMod updates on x64. There were a lot of trouble for other addons too. Remember the x64 version is a development version that might change rapidly and could be less stable.

I would like to know a few things from you:
- Are there any Lua errors? Please show me which.
- Does it happen only in single player, listen Server, a particular other server or on every server?
- Does it happen for you on windows as well?

Update: The cause of this issue has been found. It is quite involved with licensing and such, but the gmod developer might be able to fix it in the foreseeable future.

https://github.com/Facepunch/garrysmod-issues/issues/5968#issuecomment-2725358683

We have got a much better reproduction setup now. This will help developers and other community members to debug the issue in gmod and valve source engine games.

Videos, test map and reliable reproduction steps are in that post:
https://github.com/Facepunch/garrysmod-issues/issues/5968#issuecomment-2719058065

Sneak peak:
https://www.youtube.com/watch?v=hnnJDZyqt-o
https://www.youtube.com/watch?v=ICxQMo7mdSg
https://www.youtube.com/watch?v=2n6fjLcVBb0

Originally posted by Marceline:

I wont lie I forgot that this post exists (not subscribed for some reason). I'm glad i was able to bring this to your guys' attention. I hope you will be able to figure it out, as SW has always been one of my favourite series of mods.

This thread used be to in the base addon workshop discussions, which got disabled. This thread has been recreated and migrated from the old discussions.

Yesterday we made some discoveries about this issue. It also happens on other source engine games, such as CSS, TF2 and HL2:DM. HL2 is not affected. The issue is stronger if large physics objects exists on the map. I think it even happens if said large object is never interacted with. A test map for all said games and new demo videos will arrive soon.

https://github.com/Facepunch/garrysmod-issues/issues/5968#issuecomment-2708373945

New development on this issue. Apparently this problem also happens in GMod (all branches, even the main one) when its vphysics.dll is replaced by a newer version from TF2 (2025 update).

https://github.com/Facepunch/garrysmod-issues/issues/5968#issuecomment-2692725318

Hi Kaid,

I also think that it could be some kind of addon conflict or another serverside issue. I have contacted Storm37000 about this. Maybe he can help to resolve the issue.

Your post is a good start, but we need more details an that rather weird issue. So please post more details as like as asked by SligWolf.

No Problem. :D
Closed as solved.