If so, you can edit it as you want, but always respecting the license.
About the separate .cs files, the first one posted (I don't think it can be downloaded now) were completely separate files for each part of the plugin, but I merged everything into one file after all to avoid problems. (YYou can modify it, but you're still under the other EULA/SLA rules.)
EULA/SLA - License
Now talking about "Errors hit info error noticed appeared after animal killed sleeping" can you please give me the logs or send me the error that appears to you?
Since i can't replicate it right now (im not in my home at the moment), but i can try to fix it and push an update