
How do I edit the script cp_a_spawn_companion ?
I want to reverse the Tancred and Verona lines

figure out where the script is on your hardrive (it's probably in the module or campaign folder for MGS)
open it with the toolset, File|Open Conversation or Script ...
switch the lines
Compile and check it says successful.
Note. If it's in the module-folder, changes won't take effect during a current game. Unless the .nss/ncs are copied to /Override

I actually don't know how the vanilla toolset handles it, since I've almost always been using two toolset plugins that I consider indispensable -- PowerBar and Grinning Fool's Usability Tools. I think it's PowerBar that adds the script opening dialogue that I use. That one allows you to filter scripts by Campaign, Module, or Global. I'd recommend trying out those plugins if you plan to spend a lot of time in the toolset.

The script was in the campaign folder, but I couldn't open it.
re. plug-ins, Did you turn the option to use plug-ins TRUE in toolset options?
The error may mean it was made for a previous version of the toolset. It's been so long since I installed it, I don't remember if it's one of the plugins that never received an update, or received one in a pack by someone else (I remember there was a batch of updated plugins from various users posted by one other user) but you can get around the "old version" error with the "de-frus" mod.
It does go in the installation directory, but this is what mine looks like:
<?xml version="1.0"?>
<configuration>
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="OEIShared" publicKeyToken="6bb96f3d82daa243" />
<publisherPolicy apply="yes" />
<bindingRedirect oldVersion="0.0.0.0-9999.9999.9999.9999" newVersion="1.0.1765.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="SandBar" publicKeyToken="75b7ec17dd7c14c3" />
<publisherPolicy apply="yes" />
<bindingRedirect oldVersion="0.0.0.0-9999.9999.9999.9999" newVersion="1.3.4.1" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="NWN2Toolset" publicKeyToken="6bb96f3d82daa243" />
<publisherPolicy apply="yes" />
<bindingRedirect oldVersion="0.0.0.0-9999.9999.9999.9999" newVersion="1.0.1765.0" />
</dependentAssembly>
</assemblyBinding>
</runtime>
</configuration>
I can't recall if I edited any of the numbers in mine. I guess I did, because the "newVersion" is higher than the one on the Vault says it works for.
Good, I hope you find it useful. I suppose the De-frus mod needs to be updated on the Vault, or else I'll just upload my version with a name more obvious to its purpose.