Whenever I use it on a ragdoll, it doesn't make it stand. Rather it makes a "ghost"-like entity of it. I can't move it with the physgun and I can walk through it. It works on most Tf2 Models but not on the heavy for some reason and even custom TF2 Models as well.

I have videos if my explanations are hard to understand:

https://youtu.be/Xf8LL4Ed00I
https://youtu.be/smlD5bcxg0k

Also the Lua Errors read this:

[Standing Pose Tool] lua/weapons/gmod_tool/stools/ragdollstand.lua:106: attempt to index local 'matrix' (a nil value)
1. func - lua/weapons/gmod_tool/stools/ragdollstand.lua:106
2. unknown - lua/includes/extensions/net.lua:32

[Standing Pose Tool] Warning! A net message (StandPose_Server) is already started! Discarding in favor of the new message! (StandPose_Server)
1. func - lua/weapons/gmod_tool/stools/ragdollstand.lua:97
2. unknown - lua/includes/extensions/net.lua:32